Deficiency Troubleshooting

scissorsneedfoodtoo

Active Member
Hey everyone, I've got a bit of a problem on my hands. I've noticed that two of my three plants are exhibiting similar symptoms, and I'm not exactly sure what the cause is. I'm thinking Mg, but I'd really like a second opinion.

My setup is pretty simple: Black Gold soil with a bit of perlite mixed in and botanicare nutes for flowering and veg. My lighting is one of the 6, 2' bulb fixtures from HTG. All plants are bagseed and are in 3 gallon pots. My temps are around 82 F with the lights on, and the humidity is usually around 65. Proper ventalation is not possible as I live in an apartment, so I have various fans strewn around in hopes of some sort of air circulation.

The first picture shows all three plants. The one in the middle is showing mild symptoms, with mild spotting along the edges of some of the middle leaves, as seen in the second picture.

It's the third plant on the far right that I'm most worried about. I noticed a single dead spot on a middle leaf last week, but thought I may have just splashed something on it accidentally. The other day, I noticed the extreme curling and twisting that you can see.

Yesterday I watered with a gallon ph'd tap water and a 1/2 tablespoon of Epsom salt, but again, I'm not exactly sure what the problem is, and I'd like another opinion before I just make things worse.

Thanks very much for taking a look.
 

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scissorsneedfoodtoo

Active Member
Cool man, thanks for the advice. I'll be flushing ASAP. I'm pretty disappointed with the way this grow has been going recently, as my two best plants are the ones affected. What concerns me most about the plant on the far right is that it's also the one with the fewest leaves (threw them into early flowering). Think it's still salvageable?
 

bonz

Well-Known Member
how often do you water them and how much each time.
how often do you nute them.
 

scissorsneedfoodtoo

Active Member
I water them every 4 days or so, going by the weight of the pots and by the finger test. I nute every other time. Yesterday when I was flushing I took a water runoff test to find that all the plants were sitting soil in the mid to high 5 ph range. I flushed until the runoff read at least 6.6 and set them back under the light.

When I added my nutes, I would ph until 6.7, but I suppose that when running through the soil it'd get absorbed and slowly become more acid, correct? I couldn't add any lime to the soil mix to even things out as no stores carry it in bags smaller than 50 lbs, but I ordered some online. Any advice about adding lime after the fact?

Also, what should I do to compensate for the soil becomming more acid as I run nutes through? Should I raise the ph to 7 or higher to get a correct runoff reading? Will that hurt anything?

Thanks
 

bonz

Well-Known Member
sorry it took me a bit to answer, i`ve been having trouble with my computer.
anyway, have a read on this, sorry if it`s to long, just the way i have it saved.
try to keep the nute mix around 6.5


How Can I Raise or Lower the pH of my Soil Mix?


Growing in soil and adjusting pH levels
A lot of gardeners have trouble with the pH of their soil. A high pH can lock out needed nutrients and mimic other problems like Fe and Mg deficiencies. The biggest mistake new growers make is to try and correct pH problems too quickly. The first step in determining if high pH is the real problem, is to pick up a good pH tester. Don't be afraid to shell out the cash for a good one, it's well worth it!
Here are some recommendations: (All sell for under $100.00)
1. Milwaukee makes two styles of hand-held pH meters. A small "pen" called the Sharp and the larger Smart Meter. Both are easy to use. The Sharp pens are splash-proof (although not totally waterproof), and have a large easy to read display. They also have a detachable, replaceable probe.
2. Oakton - Same type of pH tester as Milwaukee makes, but it's made a little better imho. These are totally waterproof. (It floats.)
3. Shindengen ISFET pH Meters are state-of-the-art pH pens and work with a totally different method of measurement. This pen uses a solid state Ion Sensitive Field Effect Transistor (ISFET) instead of the fragile glass electrodes used by traditional pH pens. They have replaceable tips that change from opaque to clear when they need to be changed.
What is pH, and what do the terms acidic and alkaline mean?
The acidity or alkalinity of the soil is measured by pH (potential Hydrogen ions). Basically it's a measure of the amount of lime (calcium) contained in your soil, and the type of soil that you have. A soil with a pH lower than 7.0 is an acidic soil and one with a pH higher than 7.0 is considered to be alkaline. A pH of 7.0 is neutral.
Adjusting your soil pH:
Once you have determined the pH of your soil with a good tester, you can amend the soil if needed to accommodate the plants in your garden using inexpensive materials commonly available at your local garden center.
* Adjust soil pH slowly over several days time, and check pH often as you go. Radical changes in pH may cause osmotic shock damage to the roots.
Raising soil pH: (to make it more alkaline)
It is generally easier to make soil mixes more alkaline than it is to make them more acidic. The addition of dolomite lime, hardwood ash, bone meal, crushed marble, or crushed oyster shells will help to raise the soil pH.
by MisterIto
In soil: add dolomite limestone to the soil; use small amounts of hydrated lime.
Raising hydroponic pH: (to make it more alkaline)
In hydroponics:
use potassium silicate, provides silicon at an effective doseage.
In bioponics/hydro-organics: add small amounts of sodium bicarbonate or lime.
Lowering soil pH: (to make it more acidic)
If your soil needs to be more acidic, sawdust, composted leaves, wood chips, cottonseed meal, leaf mold and especially peat moss, will lower the soil pH.
by MisterIto
bloodmeal/cottonseed meal during vegetative; bonemeal during flowering.
Lowering hydroponic pH: (to make it more acidic)
In hydroponics: use nitric acid during vegetative; phosphoric acid during flowering.
Contributed by: Spiritual.Fa
Stabilizing pH with Dolomite lime
The best way to stable PH is by adding 1 ounce of Dolomite Lime per 1 gallon of planting soil.
Dolomite Lime is available in garden nurseries. Buy the fine Dolomite powder (There may be several kinds of Dolomite like Rough, Medium, Fine)
Dolomite Lime has been a useful PH stabilizer for years, since it has a neutral PH of 7 when added to your soil it stabilizes your soil at PH 7.
Mix the dry soil medium and dolomite together really well, give the mix a good watering then after the water has had chance to settle and leech into the soil a bit give the mix a really good stir. Then water the soil/lime mix and give it another stir
Best plan is to mix fine dolomite lime into your mix before planting. Fine Dolomite will help stabilize your pH; however, if the ph becomes unstable or changes, you can then use Hydrated Dolomite Lime. Add some of the hydrated lime to luke warm water and give it a good stir then water your plants with it. Give the plants a good watering with this hydrated lime added and your PH should fall or rise back to 7
Other Benefits of Dolomite Lime
Dolomite lime is also high in two secondary nutes that can often be overlooked by fertilizers; dolomite is high in both (Mg) Magnesium and (Ca) Calcium.
 

scissorsneedfoodtoo

Active Member
Thanks for all the trouble Bonz, it's much appreciated. The lime just came in the mail yesterday, but unfortunately it wasn't the fine powdered kind, so I'll need to find a way to crushi it up or grind it before use. The two plants in the front have been showing signs of recovery beyond the leaves that were already too burnt. It's the one in the back to the far right that's the most far gone. I'm considering trying to get it back on track over the next week or so, and if that doesn't work, I'll just chop it and make brownies or something.

Also, awesome journal, I'll be keeping up with your grow.
 

bonz

Well-Known Member
no problem. i dont mind helping people out.

it`s ok that it`s not the fine shit. just works faster thats all. just use what you have in the same way. it may take about a week to come back.

good luck
 
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