Woodsmaneh! Cool Growing Info

The 40/60 Phenomena


The 40/60 Phenomena are events observed during the indoor cultivation of flowering cannabis, and when using a strict 12 hour inductive photoperiod (aka 12/12). The events start with the first day of the inductive stage (12/12), and end on the day a mature crop is ready for harvest, collectively this period of time is called the Days Spent Flowering.
Stretch Phase (early flowering)
The stretch phase is a period of time during early flowering where rapid extraordinary outward growth takes place. Some growers have reported seeing 5 inches of growth in a single day during the stretch. This phase is characterized first by the extraordinary growth accompanied by longer than usual internodes, then the explosive outward growth slowly tapers off as internodes shorten. The end of the phase is signaled when growth tapers down to approximately 1/2 inch or less per day. This coincides with a time span equaling 40% of the total Days Spent Flowering. At this point growth shifts from outward to building bulk on existing growth, otherwise known as late flowering or the fattening phase.
Fatten Phase (late flowering)
The last 60% of the inductive phase is a period where outward growth is less significant. In fact, it can appear as if growth has stopped completely due to the very short internodes. During this phase a more complex set of growth activities occur. It's not much different from an apple tree that stopped producing new apples and is now devoting its remaining time to maturing or ripening the apples it already has. With female cannabis, flower production accelerates, floral clusters begin to grow wider or fatten, resin production increases and peaks, sinsemilla calyxes plump, pistils start to wither and change color, and not long after that the plant is ready for harvest.
The time-table of the stretch and fatten phases are important events for cultivators growing an unknown variety for the first time. The two most common anxieties for indoor growers during flowering of an untested variety are....

• Running out of headroom or grow space due to unanticipated growth.
• Being unable to predict the harvest date in advance.

An indoor grower with limited space, especially limited headroom, can find his plants pressing against hot lights if he doesn't take measures to plan for the explosive growth that takes place during the stretch phase. Knowing how long the stretch will last can give him that advantage. Similarly, a grower with limited time doesn't want to wait until the show is over to know when it will end. There are many things he may want to do with his time now that it's freed up from the high maintenance demands of extraordinarily fast growing plants during the stretch. Having an idea whether this period of lower maintenance will extend another 40, 60, 80, or ??? days will also help in the timely scheduling of his next crop.
The 40/60 phenomena relate to two milestones.

• The Duration of the Stretch
• Days Spent Flowering

When one of those two flowering events are known, the other two can be predicted.
You can find the calculator here
http://www.angelfire.com/cantina/fourtwenty/articles/4060.htm

halfway thru page 2. bookmarked. cool stuff here, this has potential to be a sticky, for sure. did u kknow earthworm castings are pH neutral because of a gland they go thru at the end of earthworm? i just learned that.

+reps, too.

AzaMax™

Botanical Insecticide, Miticide, and Nematicide

AzaMax is a natural product with a broad spectrum of pest control and broad plant applications. AzaMax is made from special Azadirachtin Technical extracted using patented extraction technology from Neem, a tree known for it’s innumerable benefits. AzaMax contains Azadirachtin A&B as active ingredients and more than 100 limonoids from it’s special technology. The special feature of AzaMax is that it does not use hard chemical solvents and uses food grade formulation ingredients. AzaMax is licensed in all 50 states.
AzaMax is an antifeedant and insect growth regulator and controls pests through starvation and growth disruption. AzaMax effectively controls spider mites, thrips, fungus gnats, aphids, whiteflies, leaf miners, worms, beetles, leafhoppers, scales, mealy bugs, nematodes and other soil borne pests. Best of all, AzaMax can be applied up to the time or day of harvest. The product is exempted from residue tolerance, thus there is no harmful residue on veggies, fruits, herbs and flowers etc. Truly, AzaMax is a product of Nature in tune with Technology.
Lable and directions

http://www.google.ca/search?hl=&q=a...3GGLL_en-GBCA380CA380&ie=UTF-8&aq=4&oq=Azamax

Solving Marijuana Plan Leaf Curl/Cupping Problems

OK rule number #1 when you see this happening is flush with 25% nutrients; use 2 to 3 times the pot size to do this. Flushing means lots of run-off. You use 25% because some elements are not mobile without other elements, so if you have a mag lock up flushing with water won't get the mag out, as it needs nitrogen to be mobile. Your killing your plants with kindness remember they are weeds. Here are more answers for you, you might want to save it for reference later The only time you don't use rule #1 is in the last 2 weeks of flower when bottom leaves stop being used for photosynthesis.
Unless another marijuana grower inspects the damage a true assessment might not be possible. It's hard to tell "exactly" what the culprit is. Unfortunately the “solution” the marijuana grower chooses many times is not the right one. A misdiagnosis only serves to make matters worse by promoting further decline. The ultimate and correct solution is in the hands of the marijuana grower.

Here are some common problems when marijuana leaves are curling.

1. Too much marijuana fertilizer
   The most common cause of marijuana leaf cupping aka leaf margin rolling, leaf margin burn, and leaf tip curl/burn is overzealous use of marijuana plant food. In relationship to factors such as marijuana plant vigour and rate of growth. Leaf burn is often the very first sign of too much marijuana fertilizer.
   A hard, crispy feel to the marijuana leaf frequently occurs as well, as opposed to a soft and cool feel of a happy pot leaf. Back off on the amount and/or frequency of using marijuana fertilizer. Too much marijuana fertilizer can also burn the roots, especially the sensitive root tips, which then creates another set of problems. Note - as soil dries, the concentration of the remaining salts rises further exacerbating the problem.
2. High Heat
   The marijuana plant is losing water via it’s leaves faster than what can be replaced by the root system. The marijuana leaf responds by leaf margin cupping or rolling up or down (most times up) in order to conserve moisture. A good example is reflected by the appearance of broad-bladed turf grass on a hot summer day, high noon, with low soil moisture levels - the leaf blade will roll upward/inward with the grass taking on a dull, greyish-green appearance. Upon sunrise when moisture levels have returned to normal, the leaf blade will be flat. Lower the heat in the marijuana grow-op and concentrate on developing a large robust root system. An efficient and effective root system will go a long way to prevent heat induced pot leaf desiccation or marijuana leaf margin curling. One short episode of high heat is enough to permanently disable or destroy leaf tissue and cause a general decline in the leaves affected, which often occurs to leaves found at the top of the cannabis plant. The damaged pot leaf (usually) does not fully recover, no matter what you do. Bummer in the summer. One can only look to new growth for indications that the problem has been corrected.
3. Too much light
   Yes, it’s true, you can give your marijuana plant too much light. Cannabis does not receive full sun from sunrise to sunset in its natural state. It is shaded or given reduced light levels because of adjacent plant material, cloudy conditions, rain, dust, twilight periods in the morning and late afternoon, and light intensity changes caused by a change in the seasons. Too much light mainly serves to bleach out and destroy chlorophyll as opposed to causing marijuana leaf cupping, but it often goes hand-in-hand with high heat for indoor marijuana growers. Turn down the time when the lights on in your marijuana grow room. If you're using a 24 hr cycle, turn it down to 20 hrs. Those on 18 - 6 marijuana growth cycle can turn their lights down two or three hours. Too much light can have many adverse effects on marijuana plants. Concentrate on developing/maintaining an efficient and robust root system.
4. Over Watering
   For marijuana growers using soil, this practice only serves to weaken the root system by depriving the roots of proper gas exchange. The marijuana plants roots are not getting enough oxygen which creates an anerobic condition inducing root rot and root decline with the end result showing up as leaf stress, stunted growth, and in severe cases, death. Over watering creates a perfect environment for damp-off disease, at, or below the soil line. Many times marijuana growers believe their cannabis plant is not getting enough marijuana fertilizers (which it can't under such adverse conditions), so they add more marijuana fertilizers. Making the problem worst. Not better. Often problem 1 and 4 go together. Too much marijuana fertilizer combined with too much water. Creating plenty of marijuana plant problems.
5. Not Enough Water
   Not only is the marijuana plant now stressed due to a low supply of adequate moisture, but carbohydrate production has been greatly compromised (screwed up). Step up the watering frequency, and if need be, organic marijuana growers may need to water from the bottom up until moisture levels reach a norm throughout the medium. One of the best methods in determining whether a marijuana plant requires watering is lifting the pots. The pots should be light to lift before a water session. After watering the marijuana plants lift the pots to get an understanding how heavy they've become fully watered. If the pot feels light to the lift - it’s time to water. Don’t wait until the soil pulls away from the side of the pot before watering. And of course, leach, once in a while to get rid of excess salts. These are the five most common problems marijuana growers encounter when growing cannabis. Correcting the problems early will save the marijuana plants, but may reduce overall yield. With practice and experience these problems are easily overcome which will then enable the marijuana grower to produce fantastic marijuana plants. With heavy yields.

Magnesium (Mg) - Micronutrient and Mobile Element


Magnesium helps supports healthy veins while keeping a healthy leaf production and its structure. Magnesium is significant for chlorophyll-production and enzyme break downs. Magnesium which must be present in relatively large quantities for the plant to survive, but yet not to much to where it will cause the plant to show a toxicity.


Magnesium is one of the easiest deficiencies to tell… the green veins along with the yellowness of the entire surrounding leave is a dead giveaway, but sometimes that’s not always the case here. In case you have one of those where it doesn’t show the green veins, sometimes leaf tips and edges may discolor and curl upward. The growing tips can turn lime green when the deficiency progresses to the top of the plant. The edges will feel like dry and crispy and usually affects the lower leaves in younger plants, then will affect the middle to upper half when it gets older, but It can also happen on older leaves as well. The deficiency will start at the tip then will take over the entire outer left and right sides of the leaves. The inner part will be yellow and or brownish in color, followed by leaves falling without withering. The tips can also twist and turn as well as curving upwards as if you curl your tongues.


Excessive levels of magnesium in your plants will exhibit a buildup of toxic salts that will kill the leaves and lock out other nutrients like Calcium (Ca). Mg can get locked out by having too much Calcium, Chlorine or ammonium in your soil/water.
One of the worst problems a person can have is a magnesium def caused by a ph lockout. By giving it more magnesium to cure the problem when you are thinking you are doing good, but actually you are doing more harm then good. When the plants can’t take in a nutrient because of the ph being off for that element, the plant will not absorb it but it will be in the soil… therefore causing a buildup. A buildup will be noticed by the outer parts of the plant becoming whitish and or a yellowish color. The tips and part way in on the inner leaves will die and feel like glass. Parts affected by Magnesium deficiency are: space between the veins (Interveinal) of older leaves; may begin around interior perimeter of leaf.




Watering with 1 tablespoon Epsom salts/gallon of water. Until you can correct nutrient lockout, try foliar feeding. That way the plants get all the nitrogen and Mg they need. The plants can be foliar feed at ½ teaspoon/quart of Epsom salts (first powdered and dissolved in some hot water). When mixing up soil, use 2 teaspoon dolomite lime per gallon of soil.
If the starting water is above 200 ppm, that is pretty hard water, that will lock out mg with all of the calcium in the water. Either add a 1/4 teaspoon per gallon of epsom salts or lime (both will effectively reduce the lockout or invest into a reverse osmosis water filter.
Mg can get locked-up by too much Ca, Cl or ammonium nitrogen. Don't overdo Mg or you'll lock up other nutrients

Bud Rot

Bud rot (Botrytis) is a very common worldwide fungus that attacks both indoor and outdoor crops under certain conditions. “Bud rot” is also known as “brown rot”, “grey mould” and other names. Airborne Botrytis spores can be found everywhere, all times of the year, and will attack many different species of plants. Botrytis will attack flowers, and eventually leaves and stems.

Growers running sea of green, perpetual harvest, remote grows, outdoor, or multiple strains (each with different flowering periods) should keep an eye out for Botrytis near harvest time.

Outdoor growers need to be hypersensitive to weather conditions near harvest time. Rain, morning dew, frost and cool fall nights may increase the risk of bud rot and powdery mildew.

Fully developed marijuana buds provide ideal conditions for spore germination: warm and moist plant tissues. Botrytis will initially attack the largest and densest buds in the garden, because they provide the ideal conditions for germination. Weak plants will also be attacked rapidly.

Identifying and preventing budrot

Budrot will infect and turn colas to mush in a matter of days and may destroy a crop in a week if left unchecked. Botrytis loves warm, and humid (50% or over humidity) conditions. Lowering humidity will slow and stop spore germination. Good ventilation and decent air circulation help prevent infection.
A grow room may smell noticeably moldy if Botrytis has attacked one or more colas. Once a cola has been infected, Botrytis will spread incredibly fast. Entire colas will turn to brown mush and spores will be produced, attacking other nearby colas. Ventilation may spread viable spores throughout the room.

Measures to prevent bud rot in the final stages of flowering:

Early veg and flower pruning of undergrowth to promote air circulation
Hepa filter room and intake air sources.
Introduce low levels of ozone into room air. Ozone is effective against pollen, powdery mildew and other airborne spores.
Lowering room humidity (warming nighttime air and venting frequently or using a dehumidifier)
Decreasing watering cycles and amounts to reduce room humidity
Large, dense colas should be periodically inspected. Brown tissues deep within the bud will smell mouldy and may become liquid.
Removing fan leaves during the last few days before harvest to promote air circulation

Serenade
"Serenade controls the following: ....Botrytis, Powdery mildew, Downey mildew..."

"Certified organic by OMRI and EPA/USDA National Organic Program, Serenade offers growers the luxury of application without weather or timing restrictions and there are no phyto-toxicity issues"
"To apply, simply spray on leaves and shoots to provide complete coverage. Best results will be had be pre-treating plants before signs of disease set it and then every week to protect newly formed foliage"

What if bud rot is found?
Once bud rot has been detected, the grower should isolate infected buds by removing them from the grow room immediately and harvesting the infected colas, followed by a rapid dry of the harvested colas. Take immediate steps to reduce room humidity. Afterwards, the entire crop should be carefully inspected for infection and damage. The grower may want to harvest early if more than one rotting cola has been found. Spores may have spread and are germinating deep within other colas.

Can I salvage budrot-infected colas?

Yes. Remove the infected colas from the main room, Trim out the infection (Trim more than you can see – Botrytis often infects adjacent tissues) and quick-dry them. Re-inspect buds – they should not smell mouldy.

Occasionally, using dolomite lime is warranted, but the truth is, it often makes things worse, sometimes just a little, and sometimes a lot. Let’s look at why...

What Is Dolomite Lime?
Dolomite lime is a rock. It can be quite pretty. It is calcium magnesium carbonate, CaMg(CO3)2. It has about 50% calcium carbonate and 40% magnesium carbonate, giving approximately 22% calcium and at least 11% magnesium. When you buy it for your garden, it has been ground into granules that can be course or very fine, or it could be turned into a prill. Now, dolomite lime is even allowed in organic gardening. It is not inherently bad, but how it is used in the garden is usually mildly to severely detrimental.

Why Are We Told To Use Dolomite Lime?
I have touched on this before when I talked about pH. The idea is that minerals in your soil are continuously being leached by rain and consequently your soil is always moving towards more acidic. Dolomite lime is used to counteract this, to “sweeten” the soil. It can do that, but that doesn’t mean it’s good.

Why Are Minerals Leaching From Your Soil?
Minerals may or may not be leaching from your soil. If they are, it could be partially because of rain, but there are other reasons, too. If your soil is low in organic matter, which is generally the case, it probably can’t hold onto minerals very well, especially if it is low in clay and high in sand and silt. If you have lots of clay, you probably don’t have much to worry about.
Chemical fertilizers cause acidity, so if you use them, that is part of the problem, too. Dolomite lime is not the answer. Organic gardening is. Let’s look at why dolomite is probably not what you want.

Here’s The Important Part
The main point I want to make is that even if minerals are leaching from your soil, it doesn’t make sense to blindly go back adding just two of them (the calcium and magnesium in dolomite lime) without knowing you need them. You might already have enough or too much of one or both of them. We need to think a little more than that when organic gardening.
Your soil needs a calcium:magnesium of somewhere between 7:1 (sandier soils) and 10:1 (clayier soils). Outside of this range, your soil will have water problems, your plants will have health problems and insect and disease problems, and you will have weed problems. One of your most important goals in the garden is to add specific mineral fertilizers to move the calcium to magnesium ratio towards this range. As a side note, I understand it may seem strange to some that we should have to do this, but our soils are way out of balance and we’re trying to grow things that wouldn’t naturally grow there, so we have to do this. The problem with dolomite lime? It has a calcium:magnesium ratio of 2:1. That’s way too much magnesium for most soils. Magnesium is certainly an essential mineral. Too much of it, however, causes many problems, compaction being one of the most common, but also pest and weed problems. So if you add this to your lawn every year, chances are you’re just causing more compaction and weed problems.

When Should You Use Dolomite Lime?
You should only use dolomite lime when you have a soil test showing a huge deficiency of magnesium in your soil.
Even then, calcitic lime (calcium carbonate) is generally the way to go because it has a small amount of magnesium and often a calcium:magnesium ratio of about 10:1, with a calcium content 34% to 40% or more. I use calcitic lime regularly in my organic gardening, but even then, only when I need it. A soil test is the main way to find out if you need it.

Diagnosing Nutritional Deficiencies


Texas Greenhouse Management Handbook
The correct diagnosis of nutritional deficiencies is important in maintaining optimum plant growth. The recognition of these symptoms allows growers to "fine tune" their nutritional regime as well as minimize stress conditions. However, the symptoms expressed are often dependent on the species of plant grown, stage of growth or other controlling factors. Therefore, growers should become familiar with nutritional deficiencies on a crop-by-crop basis.
Record keeping and photographs are excellent tools for assisting in the diagnosis of nutrient deficiencies. Photographs allow growers to compare symptoms to previous situations in a step-by-step approach to problem solving. Accurate records help in establishing trends as well as responses to corrective treatments.
Because plant symptoms can be very subjective it is important to approach diagnosis carefully. The following is a general guideline to follow in recognizing the response to nutrient deficiencies:
Nitrogen (N) - Restricted growth of tops and roots and especially lateral shoots. Plants become spindly with general chlorosis of entire plant to a light green and then a yellowing of older leaves which proceeds toward younger leaves. Older leaves defoliate early.
Phosphorus (P) - Restricted and spindly growth similar to that of nitrogen deficiency. Leaf color is usually dull dark green to bluish green with purpling of petioles and the veins on underside of younger leaves. Younger leaves may be yellowish green with purple veins with N deficiency and darker green with P deficiency. Otherwise, N and P deficiencies are very much alike.
Potassium (K) - Older leaves show interveinal chlorosis and marginal necrotic spots or scorching which progresses inward and also upward toward younger leaves as deficiency becomes more sever.
Calcium (Ca) - From slight chlorosis to brown or black scorching of new leaf tips and die-back of growing points. The scorched and die-back portion of tissue is very slow to dry so that it does not crumble easily. Boron deficiency also causes scorching of new leaf tips and die-back of growing points, but calcium deficiency does not promote the growth of lateral shoots and short internodes as does boron deficiency.
Magnesium (Mg) - Interveinal chlorotic mottling or marbling of the older leaves which proceeds toward the younger leaves as the deficiency becomes more severe. The chlorotic interveinal yellow patches usually occur toward the center of the leaf with the margins being the last to turn yellow. In some crops, the interveinal yellow patches are followed by necrotic spots or patches and marginal scorching of the leaves.
Sulfur (S) - Resembles nitrogen deficiency in that older leaves become yellowish green and the stems become thin, hard, and woody. Some plants show colorful orange and red tints rather than yellowing. The stems, although hard and woody, increase in length but not in diameter.
Iron (Fe) - Starts with interveinal chlorotic mottling of immature leaves and in severe cases the new leaves become completely lacking in chlorophyll but with little or no necrotic spots. The chlorotic mottling on immature leaves may start first near the bases of the leaflets so that in effect the middle of the leaf appears to have a yellow streak.
Manganese (Mn) - Starts with interveinal chlorotic mottling of immature leaves and, in many plants, it is indistinguishable from that of iron. On fruiting plants, the blossom buds often do not fully develop and turn yellow or abort. As the deficiency becomes more severe, the new growth becomes completely yellow but, in contrast to iron necrotic spots, usually appear in the interveinal tissue.
Zinc (Zn) - In some plants, the interveinal chloratic mottling first appears on the older leaves and in others, it appears on the immature leaves. It eventually affects the growing points of all plants. The interveinal chlorotic mottling may be the same as that for iron and manganese execpt for the development of exceptionally small leaves. When zinc deficiency onset is sudden, such as the zinc left out of the nutrient solution, the chlorosis can appear identical to that of iron and manganese without the little leaf.
Boron (B) - From slight chlorosis to brown or black scorching of new leaf tips and die-back of the growing points similar to calcium deficiency. Also the brown and black die-back tissue is very slow to dry so that it can not be crumbled easily. Both the pith and epidermis of stems may be affected as exhibited by hollow stems to roughened and cracked stems.
Copper (Cu) - Leaves at top of the plant wilt easily followed by chlorotic and necrotic areas in the leaves. Leaves on top half of plant may show unusual puckering with veinal chlorosis. Absences of a knot on the leaf where the petiole joins the main stem of the plant beginning about 10 or more leaves below the growing point.
Molybdenum (Mo) - Older leaves show interveinal chlorotic blotches, become cupped and thickened. chlorosis continues upward to younger leaves as deficiency progresses.
Summary
The diagnosis of nutrient deficiencies can be a key to optimizing plant growth. However, this technique is very subjective and requires careful observation. Plants respond to nutrient deficient conditions in several different ways. Growers must become familiar with these on a crop-by-crop basis. Photographs and record keeping can be very useful tools in the diagnosis of nutrient deficiencies.

First a little Plant Science 101 - For a successful, productive garden, hydroponic, indoor and greenhouse growers must control six "essential elements" - air, light, nutrients, water, humidity and temperature. Remove or alter the ratio of only one of these elements, growth will slow, and plants could eventually die. In this article, we will review the air element, specifically carbon dioxide (CO2), it's role in the most vital plant process - photosynthesis - and how to effectively implement CO2 systems.

Photosynthesis begins when stomata, pore-like openings on the undersides of leaves, are activated by light and begin breathing in carbon dioxide (CO2) from the air. This CO2 is broken down into carbon (C) and oxygen (O). Some of the O is used for other plants processes, but most is expelled back into the air. The C is combined with water to form sugar molecules, which are then converted into carbohydrates. These carbohydrates (starches) combine with nutrients, such as nitrogen, to produce new plant tissues. CO2 is vital to plant growth and development, and yet is often the most overlooked element in indoor gardening.

Successful indoor growers implement methods to increase CO2 concentrations in their enclosure. The typical outdoor air we breathe contains 0.03 - 0.045% (300 - 450 ppm) CO2. Research demonstrates that optimum growth and production for most plants occur between 1200 - 1500 ppm CO2. These optimum CO2 levels can boost plant metabolism, growth and yield by 25 - 60%.

Plants under effective CO2 enrichment and management display thicker, lush green leaves, an abundance of fragrant fruit and flowers, and stronger, more vigorous roots. CO2 enriched plants grow rapidly and must also be supplied with the other five "essential elements" to ensure proper development and a plentiful harvest.

Commercially available CO2 generators offer the most economical, practical and consistent method of enriching indoor gardens. Using atmospheric control systems in conjunction with CO2 generators, ensure the most effective production and use of CO2.

Atmospheric control systems with automatic override or defeat, and CO2 monitoring logic, enrich and maintain optimum levels in the environment during the photo (light) periods, when most plants can absorb CO2; and they defeat CO2 production during dark periods. Automating your CO2 enrichment system pays for itself quickly with shorter crop cycles, improved quality and higher yields.

When enriching an indoor garden with CO2, proper light is essential for effective assimilation. For plants to use CO2 efficiently, light spectrum and intensity should be appropriate for the plant species in your garden. Remember - CO2 enriched plants under intensified lighting demand higher levels of nutrients, water, space and room temperatures of 80-85 F. (27 - 29 C.).

As CO2 is a critical component of growth, plants in environments with inadequate CO2 levels - below 200 ppm - will cease to grow or produce. And, growers should be cautious when experimenting with CO2 levels above 2000 ppm. CO2 is heavier than oxygen and will displace the O2 required by both plants and human to function and live. (FYI: OSHA max allowable for human exposure is 5000 PPM). So, air circulation and ventilation is critical to profitable CO2 enrichment.

Plants use all of the CO2 around their leaves within a few minutes leaving the air around them CO2 deficient. Without air circulation and ventilation, the plants' stomata are stifled and plant growth is stunted.

Proper air circulation with oscillating fans and in-line blowers, will eliminate potential stagnation problems and ensure efficient CO2 enrichment.

If you have never enriched your garden with CO2, start with 700 - 900 ppm (double the normal atmospheric levels). If yields improve, increase CO2 enrichment to 1200 - 1500 ppm. If there is no response to the CO2 enrichment, double-check your other five "essential elements" to ensure they are not limiting factors.

you can do anything if you have the right knowledge

Cleaning & Sterilizing Reusable Growing Media
Aggregate media such as grow rocks, Geolite, Hydroton, etc. should be cleaned between crops to remove debris and roots that accumulated in the media. As well, any system parts that come in contact with nutrient solution, such as growing trays, feed/drain lines, water pump, etc., should be sterilized before putting the system back into use. Cleaned media can be sterilized at the same time simply by placing it in the system beforehand, or it can be sterilized separately.
It's important to note that, in spite of sterilization, any remaining root fragments will begin to disintegrate and turn brown after approximately 2-3 weeks into the next growing cycle. This will leave a brown sediment on the reservoir floor and may tint the nutrient solution with a brown color as well. Thus the cleaning procedure outlined below is intended to minimize the number of root fragments remaining in the cleaned media.

Preparation

• During harvest, leave appx 2-3 inches of the plant's mainstem sticking out of the media to serve as a handle for subsequent processing of the root ball.
• Perform the cleaning on the same day the system is put out of service, while the media is still wet and roots are still fresh. This will insure that the media sinks during the cleaning process.

Cleaning

• While grasping the root ball by the main stem, hold it inside a suitable sized empty container and shake vigorously to dislodge the media particles. Large root balls can be very tight and easily hold more than a gallon of media, so you may need to first tear the roots on the outside of the ball so those on the inside are exposed and can be dislodged more easily. From the dislodged media, remove any obvious large clumps of roots.
• Place a 5 gallon bucket in a bathtub or any suitable location with a drain. Then hook up a garden hose to your water supply and place the other end of the hose inside the bucket on the bottom. Turn on the water and allow it to constantly run so that it overflows the bucket top.
• Slowly add the loose media to the bucket (with the water still running). The media will sink to the bottom while the remaining thousands of small root fragments will rise to the top where the current of flowing water will carry them over the edge of the bucket to the drain. Stir the media occasionally to release any fragments that may have become trapped under the media. When no more roots float to the top, the media is clean and can be returned to its container .

Sterilizing
Hydrogen peroxide (H2O2) is by far the most practical product to use for sterilizing aggregate media. Unlike system parts with smooth surfaces, media such as hydroton are designed with irregular surfaces and small pores meant to capture & store nutrient solution. As a result, bleach can be flushed from smooth system parts with one fresh-water rinse, but media requires several flushes before chlorine levels in the remaining solution become safe enough for plants. This is not a concern with H2O2 as one flush is enough to return media to a safe condition. And unlike bleach, because the weak H2O2 solution will naturally breakdown to a harmless condition when exposed to air for several hours, no rinsing is required if you don't need to replant right away.
Because it is the least expensive, bleach may be more practical to use for the rest of your system. However, many find that the small savings doesn't outweigh the convenience of sterilizing both the system & media together at the same time and flushing only once, or not at all depending on the urgency to replant.
To sterilize with H2O2, you can use the same 5 gallon bucket that was used to clean the media. Fill it with 4 gallons of water, then add 2 cups (16 oz) of the common drug store variety hydrogen peroxide, this is typically a 3% solution (check the label). For other strengths use a scaled down quantity. For example, if using a 30% strength use only 1/10 or 1.6 oz. See the H2O2 page for more.
Place the container (with the media inside) into the H2O2 solution. After standing in the solution for 1 hour, remove it and let it drain back into the bucket. Rinse if needed, then repeat with the next container of media.
[h=1]Hydrogen Peroxide
Uses & Dilutions[/h]At the end of this page is an article on Oxy-Plus copied from a Usenet post. The purpose of this page is to list plant related applications H2O2 products are commonly used for, and to provide dilutions for the three most popular strengths commonly available - 3%, 17.5% and 35%.


The actual content of H2O2 in H2O2 products can vary considerably from product to product. The content is given as a percentage figure indicating how much H2O2 is actually contained within the product (also known as its purity or strength). You must read the label to know the purity of your product.
It should be noted that Oxy-Plus is a product name that is easy to confuse with other products. There is also an Oxy-Plus brand name product from Growth Technology with 17.5% H2O2 content, not the 35% content mentioned in the article on this page. It's believed the 35% solution has been revised since the article was written and is now a 17.5% solution carrying slightly modified instructions. However, there are still 35% products on the market. The dilutions from both the article and the revised instructions are compiled in the below tables along with dilutions for use with the more popular generic 3% hydrogen peroxide product commonly found in drug stores.
Oxygen-Plus is not the same as Oxy-Plus. In fact, both names seem to be commonly used with many H2O2 related products. I've seen an Oxy-Plus product meant to be taken internally by humans, another product to put in with your wash, and yet another as a mild plant food, and none stated the H2O2 content on the label. Make sure your product is suitable to be used with living plants for it may contain other ingredients harmful to plants. Look for good labeling, make sure you know which product you have and its H2O2 content.

Dilutions are given in milliliters (ml) per US Gallon and per Liter. In cases where less than one ml is used, drops will also be given as a practical alternative for dispensing such a small measure. 19 drops per ml will be used as the base, however, because drop size can vary with the dropper utensil being used it isn't very accurate. Limit the use of drops to mixing small volumes of 1 Liter or 1 US gallon or less, use milliliters whenever possible.
[TABLE="width: 55%, align: center"]
[TR]
[TD="colspan: 6"]Sterilization/Cleanup
H2O2 Dilutions
[/TD]
[/TR]
[TR]
[TD="colspan: 2"]3%
[/TD]
[TD="colspan: 2"]17.5%
[/TD]
[TD="colspan: 2"]35%
[/TD]
[/TR]
[TR]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[/TR]
[TR]
[TD]110.4ml
[/TD]
[TD]29.2ml
[/TD]
[TD]19ml
[/TD]
[TD]5ml
[/TD]
[TD]9.5ml
[/TD]
[TD]2.5ml
[/TD]
[/TR]
[TR]
[TD="colspan: 6"]850ppm H2O2 (800ppm Oxygen + 50ppm Hydrogen)
[/TD]
[/TR]
[/TABLE]


[TABLE="width: 55%, align: center"]
[TR]
[TD="colspan: 6"]Increase oxygen content in hydro systems
2-3 times a week
H2O2 Dilutions
[/TD]
[/TR]
[TR]
[TD="colspan: 2"]3%
[/TD]
[TD="colspan: 2"]17.5%
[/TD]
[TD="colspan: 2"]35%
[/TD]
[/TR]
[TR]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[/TR]
[TR]
[TD]11.0ml
[/TD]
[TD]2.9ml
[/TD]
[TD]1.90ml
[/TD]
[TD]0.50ml
9.5 drops
[/TD]
[TD]0.95ml
18 drops
[/TD]
[TD]0.25ml
4.8 drops
[/TD]
[/TR]
[TR]
[TD="colspan: 6"]87ppm H2O2 (82ppm Oxygen + 5.2ppm Hydrogen)
[/TD]
[/TR]
[/TABLE]

Note: 30-50ppm seems to be safe for hydro systems/tanks,
and up to 100ppm may to be OK for a short period of time.
Use your best judgment.
[TABLE="width: 55%, align: center"]
[TR]
[TD="colspan: 6"]Increase oxygen content in hydro systems
on a daily basis
H2O2 Dilutions
[/TD]
[/TR]
[TR]
[TD="colspan: 2"]3%
[/TD]
[TD="colspan: 2"]17.5%
[/TD]
[TD="colspan: 2"]35%
[/TD]
[/TR]
[TR]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[/TR]
[TR]
[TD]5.5ml
[/TD]
[TD]1.45ml
[/TD]
[TD]0.95ml
18 drops
[/TD]
[TD]0.25ml
4.8 drops
[/TD]
[TD]0.475ml
9 drops
[/TD]
[TD]0.125ml
2.4 drops
[/TD]
[/TR]
[TR]
[TD="colspan: 6"]44ppm H2O2 (41ppm Oxygen + 2.6ppm Hydrogen)
[/TD]
[/TR]
[/TABLE]


[TABLE="width: 55%, align: center"]
[TR]
[TD="colspan: 6"]Seed Germination
Treating Rockwool
Misting Solution
H2O2 Dilutions
[/TD]
[/TR]
[TR]
[TD="colspan: 2"]3%
[/TD]
[TD="colspan: 2"]17.5%
[/TD]
[TD="colspan: 2"]35%
[/TD]
[/TR]
[TR]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[TD]US Gallon
[/TD]
[TD]Liter
[/TD]
[/TR]
[TR]
[TD]34.8ml
[/TD]
[TD]9.2ml
[/TD]
[TD]5.97ml
[/TD]
[TD]1.578ml
[/TD]
[TD]3ml
[/TD]
[TD]0.789ml
15 drops
[/TD]
[/TR]
[TR]
[TD="colspan: 6"]273ppm H2O2 (257ppm Oxygen + 16ppm Hydrogen)
[/TD]
[/TR]
[/TABLE]

If you want to further convert into ounces, cups, etc. use this liquid conversion chart.
[h=2]The 35% article as posted to Usenet[/h]Oxy - Plus contains 35% Hydrogen Peroxide (H2O2) in a stabilised form. H2O2 is highly oxygenating in action. It is a chemical which is fundamental to life itself, participating in many of the metabolic processes in plants and animals. When added to the nutrient tank it will quickly break down into pure water, releasing the extra Oxygen ion into the solution where it can be taken up by the roots in much the same way as nutrient ions.
In plants the extra Oxygen provided will massively stimulate protein production at the cellular level. This will greatly enhance the photosynthetic process, leading to bushier plants with larger leaves, thicker stems and shorter internodes. Plants will be stronger and leaves will be darker, thus collecting light with greater efficiency and further improving photosynthetic response.
Oxy - Plus has many applications in the greenhouse or growroom. It can be used to improve germination of seeds and to increase strike rates of cuttings. It can be added to the nutrient tank and also used as a Foliar feed. Finally it can be used at the end of the season to disinfect the system and to clear out decaying organic material from growing media.
Test Strips.
Used to monitor levels of Oxy-Plus in nutrient solutions. Strips are easy to use and show a wide range from 1 - 100 ppm H2O2. These readings will allow the easy monitoring and maintenance of effective levels of H2O2 in the nutrient tank. Optimum level for hydroponic systems is 30 - 100 ppm H2O2.
Growing with H202 35%
OXY-PLUS is just one of a number of high performance Growth Enhancers now available to the dedicated grower. These instructions are based on a range of agents, including Oxy-Plus which work best together. In all cases Oxy-Plus can be used on its own for the applications suggested. In all cases it is important to stick to the recommended dosage. Oxy-Plus is a very powerful chemical and higher doses can be harmful to plants.
MORE IS NOT ALWAYS BETTER

INSTRUCTIONS FOR USE
Seed Germination
To a Litre of lukewarm water add;
15 drops Oxy-Plus
5 mls ( 1 teaspoon) Nitrozyme
Stir thoroughly. Soak seeds in this solution for 24 hrs. before germinating in the usual way. Seeds treated in this way will germinate faster and produce more vigorous seedlings.
Cuttings (Clones)
Stock plant (mother).
Stock plant should be sprayed or misted with Nitrozyme about two weeks before cuttings are to be taken. This will produce a flush of vigorous new shoot growth and provide plenty of material for cuttings.

To each Litre of lukewarm water add;
5 mls ( 1 teaspoon) Nitrozyme
1 - 2 mls Agral.
15 drops Oxy-Plus

Mist stock plant thoroughly with this mixture. Apply when light levels are low, early morning is best time.
Treating RockWool
Take an appropriate amount of lukewarm water. Adjust pH to 5.5.
For each Litre add;
15 drops Oxy-Plus
5 mls Nitrozyme

Allow RockWool cubes to soak in this solution until thoroughly saturated. Set aside to drain.

Take cuttings in the usual way. Most species are propagated best from softwood tips. Selected material should show signs of healthy vigorous growth. Stems should be thick and firm and foliage should be dark green. We highly recommend Clonex Hormone Rooting Gel as the best product for root initiation.

Once all cuttings are in place, mist them thoroughly;
For misting solution,
to each Litre of lukewarm water add;
5 mls ( 1 teaspoon) Nitrozyme
1 - 2 mls Agral.
15 drops Oxy-Plus
To encourage speedy root initiation on your cuttings, it is necessary to pay attention to the environment in which this is taking place......Cuttings need to be kept in a very humid environment and will benefit from frequent misting. Best way to ensure ideal rooting environment is to use a propagator with a heated base and a high clear plastic cover. Keep cover on for at least three days then begin to open vents. Mist regularly with Nitrozyme Foliar as above.

Hydroponic Systems
To each 10 Litres of Tank Volume add;
5 mls ( 1 teaspoon) Nitrozyme
2.5 mls.Oxy-Plus
5 mls Earth Food
Stir thoroughly before circulating to plants.
Oxy Plus should be added to tank two or three times a week to maintain optimum levels of free Oxygen in the solution. Test strips are available to assist the grower in this (see your Hydroponic retailer).
This info was included in the revised instructions, this is as good a place as any to include it.
Quote: "If it's convenient to add Oxy-Plus on a daily basis, then it should be added at the rate of 5ml per 20 Liters of tank volume."
The revised instructions are for use with the 17.5% Oxy-Plus product. For using on a daily basis with the 35% product, simply halve the quantities just mentioned to 2.5ml per 20 liters of tank volume)
Foliar Feeding Rocket Fuel
Foliar feeding is the most efficient way to maximise benefits from these extraordinary natural growth enhancers. University studies have shown that correctly applied Foliar nutrition can be up to TEN times as useful to the plants as dry fertilisers. The following recipe is widely used in California where it is considered the ultimate growth booster and is affectionately known as Rocket Fuel.

To each Litre of water pH 6, slightly warmed, add the following ingredients, stirring or shaking thoroughly between each new addition.
1. 15 drops Oxy-Plus
This will remove any Chlorine and increase level of Oxygen availability, improving nutrient uptake and usage in plants.
2. 36 drops Agral.
3. 5 mls Nitrozyme
4. 30 mls Earth Food
Shake mixture thoroughly and mist the entire plant. Plants should be treated in this manner every two to three weeks and definitely no more than once a week. Foliar feeding should ALWAYS be carried out in low light, early morning or late evening. The above solution can also be used to water the root zone of plants. First dilute the mixture with four volumes of water. (One Litre of the above mixture will therefore make up to five Litres of watering solution).

Cleanup
Oxy-Plus can be used to clean and sterilise your hydroponic system and growing medium. It is a powerful and very aggressive liquid and it will effectively kill all pathogens and harmful bacteria. After application it will rapidly break down to harmless substances and there is no risk of damage to future crops. For this reason Oxy-Plus is a much better material for sterilisation than Hypochlorite.
If you are using a medium such as Perlite or expanded clay you will need to remove as many of the old roots as possible. You can then soak the medium in a concentrated solution of Oxy-Plus. This will oxidise organic matter in the medium and assist in its rapid decomposition. Remember to flush medium with fresh water before re-use. You can also make up Oxy-Plus in the tank and circulate it around the system to sterilise all the pipework, drippers etc. Once again remember to flush the system thoroughly with fresh water before installing new plants.
For cleanup solution
To each 10 Litres of Tank Volume add;
25 mls Oxy-Plus

Attention
Oxy-Plus is highly concentrated. The active ingredient is a volatile and aggressive chemical. Treat Oxy-Plus with great caution and handle with due care. KEEP OUT OF REACH OF CHILDREN.

oftheCosmos said:

Amazing thread and beautiful flowers
Subbed +rep

Click to expand...

Thanks for stopping by

[TABLE="width: 100%"]
[TR]
[TD]What is the difference between ppm and EC?
[/TD]
[TD][/TD]
[/TR]
[/TABLE]
Total Dissolved Solids (TDS) is the best measurement of the nutrient concentration of a hydroponic solution. To estimate TDS, one can use a meter that measures the Electric Conductivity (EC) of a solution, and convert the number to TDS in parts per million (ppm). Many meters will do this conversion.

Total dissolved solids (TDS) is typically expressed in parts per million (ppm). It is a measurement of mass and determined by weighing, called a gravimetric analysis. A solution of nutrients dissolved in water at a strength of 700 ppm means that there are 700 milligrams if dissolved solids present for every liter of water. To accurately calculate total dissolved solids (TDS), one would evaporate a measured filtered sample to dryness, and weigh the residue. This type of measurement requires accurate liquid measurement, glassware, a drying oven, and a milligram balance. Example: 50 mL of the 700ppm solution would leave 35 mg of salt at the bottom of a crucible after drying.

Electrical Conductivity (EC) is expressed in siemens per centimeter (s/cm) or milliseimens per centimeter(ms/cm). It can be determined with an inexpensive hand held meter. Nutrient ions have an electrical charge, a whole number, usually a positive or negative 1, 2, or 3. EC is a measurement of all those charges in the solution that conduct electricity. The greater the quantity of nutrient ions in a solution, the more electricity that will be conducted by that solution. A material has a conductance of one siemens if one ampere of electric current can pass through it per volt of electric potential. It is the reciprocal of the ohm, the standard unit of electrical resistance. A siemens is also called a mho (ohm backwards).

For convenience, EC measurements often are converted to TDS units (ppm) by the meter.

The meter cannot directly measure TDS as described above, and instead uses a linear conversion factor to calculate it. Everyone’s nutrient mix is different, so no factor will be exact. The meter uses an approximate conversion factor, because the exact composition of the mix is not known. Conversion factors range from .50 to .72, *depending on the meter manufacturer, which do a good job of approximating a TDS calculation from the meter’s measurement of EC.

* All ppm pens actually measure the value based on EC and then convert the EC value to display the ppm value, having different conversion factors between differing manufacturers is why we have this problem communicating nutrient measurments between one another.

EC is measured in millisiemens per centimeter (ms/cm) or microsiemens per centimeter (us/cm).

One millisiemen = 1000 microsiemens.

EC and CF (Conductivity Factor) are easily converted between each other.
1 ms/cm = 10 CF

"The communication problem"...
So again, the problem is that different ppm pen manufacturers use different conversion factors to calculate the ppm they display. All ppm (TDS, Total Dissolved Solids) pens actually measure in EC or CF and run a conversion program to display the reading in ppm's.

There are three conversion factors which various manufacturers use for displaying ppm's...

USA 1 ms/cm (EC 1.0 or CF 10) = 500 ppm
European 1 ms/cm (EC 1.0 or CF 10) = 640 ppm
Australian 1 ms/cm (EC 1.0 or CF 10) = 700 ppm

For example,
Hanna, Milwaukee 1 ms/cm (EC 1.0 or CF 10) = 500 ppm
Eutech 1 ms/cm (EC 1.0 or CF 10) = 640 ppm
Truncheon 1 ms/cm (EC 1.0 or CF 10) = 700 ppm

Calculating the conversion factor
If your meter allows you to switch between EC and TDS units, your conversion factor can be easily determined by dividing one by the other.

Place the probe in the solution and read TDS in ppm. Change to EC on the meter and read EC in ms/cm.

Conversion factor = ppm / ec.
[Note: ms must be converted to us: One millisiemen = 1000 microsiemens (1.0 ms/cm = 1000.0 us/cm)

According to the chart below:
1.0 ms/cm = 500 ppm (USA Hanna)
1000 us/cm = 500 ppm

Conversion factor = ppm / (ms/cm * 1000)
.50 = 500ppm / (1000us/cm) ]

The answer is your meter's convertion factor and should be a number between 0.50 and 0.72 To improve accuracy, take ec and ppm readings from your res daily for about ten days. Average the conversion factors. The more data points that you use, the closer you will be to finding your true conversion factor.

When reporting your PPM in a thread, please give the conversion factor your meter uses. For example: 550 PPM @0.7 or give the reading in EC, which should be the same meter to meter.

It may also be advisable to give the starting value of your water; there is a huge difference between RO and distilled water with a PPM of approximately 0 and hard tap water of PPM 300 @.5 (notice the conversion factor so others can work out the EC) or well water with a conductance of 2.1 ms/cm.


A note to Organic Growers:
An EC meter has fewer applications for a soil grower because many organic nutrients are not electrically charged or are inert. Things like Superthrive or Fish Emulsion, blood meal, rock phosphate or green sand cannot be measured with a meter reliably when they are applied or in runoff. Meters can only measure electrically charged salts in solution.

"The solution"...
When reporting your PPM in a thread please give the conversion factor your meter uses for example 550 PPM @.7 or give the reading in EC (the EC shoul d be the same meter to meter).

Oxygenation, Air Pumps, Nutrient Uptake and Temperatures

Introduction: Why plant roots need oxygen
Oxygen is an essential plant nutrient - plant root systems require oxygen for aerobic respiration, an essential plant process that releases energy for root growth and nutrient uptake. In many 'solution culture' hydroponic systems, the oxygen supplied for plant root uptake is provided mostly as dissolved oxygen (DO) held in the nutrient solution. If depletion of this dissolved oxygen in the root system occurs, then growth of plants, water and mineral uptake are reduced. Injury from low (or no) oxygen in the root zone can take several forms and these will differ in severity between plant types. Often the first sign of inadequate oxygen supply to the roots is wilting of the plant under warm conditions and high light levels. Insufficient oxygen reduces the permeability of the roots to water and there will be an accumulation of toxins, so that both water and minerals are not absorbed in sufficient amounts to support plant growth. This wilting is accompanied by slower rates of photosynthesis and carbohydrate transfer, so that over time, plant growth is reduced and yields are affected. If oxygen starvation continues, mineral deficiencies will begin to show, roots die back and plants will become stunted. If the lack of oxygen continues in the root zone, plants produce a stress hormone - ethylene, which accumulates in the roots and causes collapse of the root cells, at this stage pathogens such as pythium can easily take hold and destroy the plant.

Oxygen in Hydroponic Nutrient Solutions
While it’s possible to measure the levels of dissolved oxygen in a hydroponic nutrient solution, it’s not carried out as often as EC and pH monitoring due to the cost of accurate DO (Dissolved Oxygen meters). However, if an effective method of aeration is continually being used, and solution temperatures are not reaching excessively high levels, then good levels of oxygenation in most systems can be achieved One of the most common and effective methods of oxygenation in hydroponic nutrient solutions is with the use of air pumps/machines and air stones.

Air Pumps and Air Stones
While there are a number of methods that can be used to introduce oxygen into a nutrient solution, many of these, such as ozone treatment, are expensive and not often used by smaller growers. One of the most practical and inexpensive, yet efficient ways of getting more dissolved oxygen into a plants root system is through forcing air into the nutrient. Air pumps are widely available in a range of sizes, from very small up to very large with capacity to run from one to many `air stones’ each introducing hundreds of tiny bubbles of fresh, oxygen rich air into the nutrient solution.

Why an Air Stone
While an air pump tube alone can bubble air into a nutrient solution, oxygenation or the process of getting atmospheric oxygen dissolved into the liquid nutrient, is much more effective where many tiny bubbles of air are created, rather than a slow stream of larger bubbles. The greater the surface contact between the air bubbles and the nutrient, the more oxygen will diffuse into the nutrient solution and smaller bubbles create a far greater surface area than a few larger bubbles will. Air stones simply break up the air flow and distribute along the surface of the porous 'stone' so that many tiny bubbles are rapidly introduced into the nutrient. Depending on the size or dimensions of the nutrient reservoir into which air is being introduced for oxygenation, air stones of different shapes and sizes can be selected. For small rectangular tanks, long thin air stones (some up to 1 foot in length) can be placed on the base of the reservoir to distribute air bubbles and oxygen uniformly. A larger number of smaller, round, cylindrical or oval air stones placed at equal distance inside a nutrient pool or tank also ensure high levels of oxygenation.
Air stones also have the benefit of acting as 'weights' which remain stable on the base, or in the lower layers of the nutrient tank - the further the bubbles have to travel to reach the surface of the nutrient, the more time oxygen has to diffuse into the liquid and the higher the rates of dissolved oxygen than can be obtained from an air pump and stone set up.
For systems with multiple nutrient reservoirs or tanks, one large air pump with many outlets will allow oxygenation into all systems and it is always a good idea to buy an air machine and air stones larger than currently required so that aeration can be increased under warmer conditions or if the hydroponic system is later expanded.

Oxygen and Temperature Effects - Effective Aeration
While forcing air bubbles deep down into the nutrient reservoir generally increases the dissolved oxygen levels in the nutrient, there is one other major factor to consider and that's the temperature of the air being pumped into the nutrient. As the temperature of a nutrient solution increases, its ability to hold dissolved oxygen decreases. So a cool nutrient solution may in fact hold twice as much oxygen at 'saturation level' than a warm solution. For example a nutrient solution at 45 F can hold around 12ppm of dissolved oxygen at 'saturation', (meaning it is the most it can hold), but the same nutrient solution at a temperature of 85 F will hold less than 7ppm at saturation. This means at a solution temperature of 85F there is much less dissolved oxygen available for the plant’s root system to take up. To complicate matters further, the requirement of the plant’s root system for oxygen at warmer temperatures, is many times greater than at cooler temperatures due to the increased rate of root respiration. So warm nutrients mean a very high oxygen requirement from the plant’s roots, but the nutrient can only hold very limited amounts of dissolved oxygen at saturation, no matter how much air is being bubbled into the solution. Ideally, nutrient solution temperatures for most plants should be run lower than the overall air temperature - this has many beneficial effects on plant growth and development. However, if overly warm air from the growing environment is pumped into an otherwise cool nutrient solution, the warm air will rapidly increase the temperature of the nutrient to that of the growing environment. If air is being pumped via an air machine with an intake close to lights or other heat sources then rapid heating of the nutrient will occur. On the other hand, cool air has the ability to reduce the temperature of the nutrient if sufficient levels are pumped in and thus result in a much more highly oxygenated solution for the plant’s roots. If keeping the nutrient solution temperature down seems to be a continual problem, checking the air inlet temperature of an air pump is a good idea. Overly warm nutrient solutions (ideally nutrient solutions should remain below 65 - 75 F) for most warm season, high light plants and well below 69 F for cool season can have serious effects on the plants root system. Apart from the increased oxygen requirement due to a much higher rate of root respiration which can rapidly result in oxygen starvation, high solution temperatures favour many of the root disease pathogens. Plant roots become highly 'stressed' when experiencing high temperatures, particularly if there is a large mis-match between the air and root temperature. Root stress slows the development of new roots, resulting in reserves inside the root tissue being `burned up’ during respiration faster than they are accumulated, and stress makes the root system in general more susceptible to disease attack. Keeping a check on nutrient temperature is vital, as is ensuring that air machines are not blasting hot air into the solution and cooking plant roots. Aeration is most effective when cool air is bubbled into a nutrient.

Oxygenation and Nutrient Uptake
Healthy roots supplied with sufficient oxygen are able to absorb nutrient ions selectively from the surrounding solution as required. The metabolic energy which is required to drive this nutrient uptake process is obtained from root respiration using oxygen. In fact there can be a net loss of nutrient ions from a plant’s root system when suffering from a lack of oxygen (anaerobic conditions). Without sufficient oxygen in the root zone, plants are unable to take up mineral nutrients in the concentrations required for maximum growth and development. Maintain maximum levels of dissolved oxygen boosts nutrient uptake by ensuring healthy roots have the energy required to rapidly take up and transport water and mineral ions.
Calcium is one important nutrient ion which has been shown to benefit from high levels of oxygenation in the hydroponic nutrient solution Calcium, unlike the other major nutrients is absorbed mostly by the root growing tips (root apex). The root apex has a large energy requirement for new cell production and growth and is therefore vulnerable to oxygen stress If root tips begin to suffer from a lack of oxygen, a shortage of calcium in the shoot will occur. This shortage of calcium makes the development of calcium disorders such as tip burn and blossom end rot of fruit more likely and severe under oxygen starvation conditions. High levels of oxygenation ensure healthy root tips are able to take the levels of calcium required for new tissue growth and development.

Conclusion
While providing oxygenation with the use of air machines and stones is an excellent method of increasing the dissolved oxygen (DO) levels in a nutrient solution, the temperature of the air intake and nutrient solution must also be managed to ensure oxygen starvation in the root zone does not occur. Pumping hot air into a nutrient not only creates temperature stress in the root zone, it also results in less oxygen carrying capacity in the solution itself - a recipe for root suffocation that will rapidly affect the top portion of the plant as well. Getting oxygenation right means checking both aeration capacity of the equipment being chosen and temperatures in the nutrient and root zone.

Low Maintenance Mothering

Stasis & Selective Light Intensity

Using clones of a favorite plant is the best way to perpetuate the traits we like most about that plant. It also helps bring some uniformity to a garden so we can rest assured that all the plants grow in the same manner and at the same rate. For the Sinsemilla cultivator one of the best things about using clones is that it removes the anxiety ridden step of sexing plants, eventually culling the males, then growing whatever females Mother Nature has seen fit to leave us with. Unlike seeds, using clones requires a living plant from which cuttings can be taken. While cuttings can be taken from a crop destined to be harvested, many people don't want to compromise their producers and will designate a separate plant to be the mother for their next generation of clones. Because a vegetative phase is more conducive to taking cuttings, and generally used for rooting them, a separate space is set up to isolate plants receiving a flowering photoperiod from those receiving a vegetative photoperiod. The vegetative space occupied by the mother plant(s) will need to be maintained separately. Timing the plant's growth in such a way as to deliver enough cuttings, at the right time, and of a good quality is of the essence. The need for cuttings develops as a crop nears harvest. Advance time must be allowed for the cuttings to root well so their placement in the system will coincide with the timely harvesting of the flowering plants. This means that a mother plant will be growing for almost the entire duration of a crop before her services are ever needed again. Under the wrong conditions this length of time (e.g. 60-90 days) can produce a mother plant that will easily outgrow its allotted space, or demand your time in order to maintain the growth within the space limitations. This hands-on maintenance usually takes the form of removing or redirecting growth. What's described here are two methods of reducing growth so that the time spent using hands-on methods can be eliminated.


Vegetative photoperiods generally range from a constant 24 hours to 16 hours of light per day. Its goal is to prevent the plant from flowering, thus for mothers, providing good vegetative stock for cuttings. Needless to say 16 hours of light per day will produce less growth than more hours will, so for purposes of growth reduction fewer hours of light per day is preferable. Because the flowering response of cannabis is triggered by the duration of the dark phase, it will flower when it receives 12 hours of uninterrupted darkness, but it will not flower with 12 hours of interrupted darkness. Manipulating light timer settings in such a way as to provide 12 hours of light over a 24 hour period, but not permitting 12 hours of uninterrupted darkness to occur, can reduce growth by 25% when compared to the traditional 16 hour vegetative photoperiod without triggering the flowering response. A timer capable of 4 on/off cycles per day, using the settings in the following table, will produce such results.

[TABLE="width: 40%, align: center"]
[TR]
[TD="colspan: 2"]Timer settings for a 24 hour period
beginning at 7pm
[/TD]
[/TR]
[TR]
[TD]ON
[/TD]
[TD]OFF
[/TD]
[/TR]
[TR]
[TD]7 pm
[/TD]
[TD]6:00 am
[/TD]
[/TR]
[TR]
[TD]9 am
[/TD]
[TD]9:20 am
[/TD]
[/TR]
[TR]
[TD]1 pm
[/TD]
[TD]1:20 pm
[/TD]
[/TR]
[TR]
[TD]4 pm
[/TD]
[TD]4:20 pm (off til 7 pm)
[/TD]
[/TR]
[/TABLE]


As you can see from the below graphic, over a 24 hour period these timer settings will provide 12 hours of light and 12 hours of darkness, but will not trigger flowering because no single dark phase is long enough to do so.





Because a stasis photoperiod requires multiple on/off light cycles per day, it's best applied using fluorescent lighting, rather than stress HID lighting system components with so many daily on/off cycles. It also makes sense that if one wants to reduce growth that he would opt for lighting that provides fewer lumens. Unlike HID lighting, fluorescent lighting often uses multiple bulbs to distribute light over a given area. Configuring a multiple fluorescent lamp set-up so that each light can independently be turned on or off allows a grower to not only control the duration of the light per day with a stasis photoperiod, but to also control the light intensity.
Selective light intensity with fluorescents is nothing more than using as few tubes (less light) as needed to keep growth to a minimum during the times cuttings are not needed, and using more tubes (more light) just prior to taking cuttings so that shoots used for cuttings will be more robust and make for better clones. Turning off half of the available lamps during this time can reduce growth by 50%.
The combined growth reduction from using stasis and selective light intensity can approach 75%. The benefit is that the time spent on manual hands-on mother maintenance is replaced by the flick of a few switches.

http://www.angelfire.com/cantina/fourtwenty/articles/mothering.htm

You must spread some Reputation around before giving it to woodsmaneh! again.

Thanks for the great thread! If you have anymore great articles please carry on posting alot of good information in them!!!

Molasses and Plant Carbohydrates - b.com]Texas Plant & Soil Lab Report

The following is an article I found on molasses and its use with plants. Thought others might find it useful, I did.

“Molasses and Plant Carbohydrates”
Sugars relating to plant functions for maximum economic production.
Texas Plant & Soil Lab, Inc., Texas Plant & Soil Lab (Home)

Environmental factors that affect when and how much sugar to use:
a. How much nitrate is in the soil, and plant sap (petiole test).
b. Soil moisture conditions.
c. Sunlight intensity.
d. Temperature.
e. Wind
f. Fruiting stage / load
g. Growth / vigor [shade lower leaves]

The right amount at the right time can improve fruiting and produce normal
plant growth with less attraction for disease and insects.

Needed for healthy plants - fruit production - plant development &
maturity.
Roots take nutrients from the soil and transport them up the stalk thru the
petiole (stem) to the leaves where the sunlight aids the production of
photosynthates (sugars are not the ONLY product of photosynthesis)
carbohydrates (C, H & O), principally glucose (C6H12O6) and then other sugars and photosynthates are formed.

Plant Sugars and other photosynthates are first translocated (boron is essential to the translocation) to a fruiting site. If fruit is not available, the sugars, along with excess nitrates, spur the rapid vegetative growth of the plant at the expense of creating fruiting bodies (first sink) for the storage of the sugars.

Once the proper balance of environmental factors (heat units, light intensity, soil moisture, nutrient balance, etc) are met, the fruiting buds form and then fruit formation gets the first crack at the sugar supply.

Any excess sugars are then translocated to the number two sink, (growing terminals,) to speed their growth. The left-over sugars, etc. then go to the number 3 sink, (the roots,) to aid their growth. Here the new root hairs take up nutrients to help continue the cycle of sugar and other photosynthate production, fruiting, growth of terminals and roots.

ADDED SUGARS CAN AID THE PLANT IN SEVERAL WAYS:
- MOLASSES is probably the best outside source of many sugars, such as table sugar, corn syrup and several more complex sugars such as polysaccharides found in humus products.
- Sugar can be added to the soil in irrigation water, drip & pivot being the most effective.

In the soil it can:

- Feed microbes to stimulate the conversion of nitrates to the more efficient NH2 form of N to synthesize protein more directly by the plants.

- The roots can directly absorb some of the sugars into the sap stream to supplement the leaf supply to fruit where it is most needed, and ALSO directly feed the roots for continued productive growth.

- This ADDED sugar can also help initiate fruiting buds in a steady-slow
fashion while maintaining normal growth.

-EXCESSIVE amounts of ADDED SUGARS applied foliarly can shock the
plant resulting in shortened growth internodes, increased leaf maturity & initiation of excess fruiting sites. This can be a short term effect lasting only a few days.

Pollination, soil moisture, nutrient balance and sufficiency as well as adequate light for photosynthate production decide how much of the induced fruit can mature.

woodsmaneh! said:

Thanks for stopping by

Click to expand...

baby I'm amazed

wow, great info. plus REP for you. time to get back to work...