Earth Juice Natural PH Up - how might it impact the benefiscial microbes?
- Thread starter pickmybud
- Start date
Cannabisworks
Active Member
no ph solution effects microbes or organic foods. and all food forms need pH to get the most from the grow.
Cannabisworks
Active Member
buffer doent mean no need to ph. buffer means slows the move of this not no need for it. google buffer
Icemud
Well-Known Member
excuse my choice of vocab...not buffer....the soil microbes will adjust the ph to near neutral in organics...some microbes seek positive ions while others see negative ones....they work together with the roots to balance the soil ph to a acceptable level. By adding PH adjustment solutions, you possibly may be killing and/or reducing the amount of soil microbes that break down the soil into usable ions for the plants.... I wouldn't suggest any PH adjustment with organics...If you are running salt based fertz, then by all means ph adjust...
Cannabisworks
Active Member
well from a maker of nutes ph doesnt harm the bennies. the bennies give off ph up or down depending if its day or night and if they feed or rest.
most solutions we buy in the store arent even organic anyways. most are organic based. or the ph in them would be way low. the reason people thought they dont need to ph organics is because a plant cant eat the organic form food yet. so slowly the microbes eat this food and shit it back out in a food form. htis is hwy no burns as this is such a slow process. some real organics arent avail for months after. dont be fooled by the omri stamp. means nothing. a true organic food is real low like 3 ph and if you didnt use ph up your plant would be dead by morning.
the microbes to help with the ph buffering as it goes by what ellement of food they ate and form of poop that came out and this all regulates it. if you ph then there is more food available sooner and easier for the whole process thus makinbg you need less food to get the same end result so its saving the grower money. sure you dont have to use ph. as its sucjh a slow process so wont burn. but it sure makes fir a better grow.
ive yet to see any facts from a rep place that says nobody needs ph in organics. ive asked and asked for it but havent seen any yet. but yet tons of whole web site devoted to just this alone
most solutions we buy in the store arent even organic anyways. most are organic based. or the ph in them would be way low. the reason people thought they dont need to ph organics is because a plant cant eat the organic form food yet. so slowly the microbes eat this food and shit it back out in a food form. htis is hwy no burns as this is such a slow process. some real organics arent avail for months after. dont be fooled by the omri stamp. means nothing. a true organic food is real low like 3 ph and if you didnt use ph up your plant would be dead by morning.
the microbes to help with the ph buffering as it goes by what ellement of food they ate and form of poop that came out and this all regulates it. if you ph then there is more food available sooner and easier for the whole process thus makinbg you need less food to get the same end result so its saving the grower money. sure you dont have to use ph. as its sucjh a slow process so wont burn. but it sure makes fir a better grow.
ive yet to see any facts from a rep place that says nobody needs ph in organics. ive asked and asked for it but havent seen any yet. but yet tons of whole web site devoted to just this alone
TheOrganic
Well-Known Member
Humboldt Organic full line up 3gal fabric and never tested PH, Just PPM. First pic...Pineapple express is the size of a beer bottle for main cola. And blue hash thats leaning over(2pics) is tennisball size nugs. I'm not a rep but I know I don't need to test ph. Shitz Fiya.
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Icemud
Well-Known Member
Here is my current grow... I haven't ph checked or balanced at all since clone...I haven't even checked the ppm's... I feed them distilled water with Full Earthjuice line(grow, bloom, meta-k, catalyst, and micro) along with General organics BioWeed(cold pressed Algae), Bioroot and Cal/Mag along with Adv Nutr. liquid carboload, F1 Fulvic acid, H-2 humic acid...I have no lime whatsoever besides what came in FFOF and happyfrog....and so far no leaf tips burnt, no discoloration, no issues whatsoever and I have not even checked my PH once...
And here is a few pics of my organic nugs last grow...after locking out 2x with ph adjusting...during flower I stopped adding adjustments and here is the results...
And here is a few pics of my organic nugs last grow...after locking out 2x with ph adjusting...during flower I stopped adding adjustments and here is the results...
pickmybud
Member
Thank you everyone for your responses. Yet another fine example of the age-old debate as to whether one should PH adjust their organice nutrients or not.
Icemud - I use EJ as well and would LOVE to not have to bubble into a tea every single time I feed. Do you just "mix and feed" the way the company suggests? When I do that the PH of the mix drops to 4.0-ish and that scare the heck out of me so I bubble into a tea to get it in range (6.5 +/-). I am starting a new grow soon and may try that method on one of the plants to see how it goes. Any words of knowledge regarding how often you feed, whether you go strong or light in your mix, etc?
I am also going to try a few plants with water only - using a slight modified version of subcool's mix.
Thanks again all.
Icemud - I use EJ as well and would LOVE to not have to bubble into a tea every single time I feed. Do you just "mix and feed" the way the company suggests? When I do that the PH of the mix drops to 4.0-ish and that scare the heck out of me so I bubble into a tea to get it in range (6.5 +/-). I am starting a new grow soon and may try that method on one of the plants to see how it goes. Any words of knowledge regarding how often you feed, whether you go strong or light in your mix, etc?
I am also going to try a few plants with water only - using a slight modified version of subcool's mix.
Thanks again all.
Cannabisworks
Active Member
for those that dont understand food again in here and ph...and those nutes have ph already in the bottle to make it stable. it has to or there is no shelf life. and is only organic based as i already said most on the market are. derived from dont make it organic and all that stuff on humbolts says dervived from and final form is all same as a synthetic nute. read the label....lol all it needs a 17% organic content to get a stamp of organic or from omri., omri disent even test for the base entry/. there are diff classes within omri classifications. its a government money grab. anbd that i have first hand exp on dealing with omri
ive asked and asked for this fact info to say soil dosent need to be ph`d. 4 or 5 threads in here now and im still waiting. so heres a bit for those that have the desire to learn
Soil pH | Nitrogen | Phosphorus | Potassium | Sulfur | Micronutrients Farmers frequently ask, "What effect does pH have on availability of nutrients in the soil?" There is no simple answer to this question, since the effects of pH are complex and vary with different nutrients. However, some broad generalizations are useful to keep in mind when making nutrient management decisions.
Soil pH
The first order of business is a quick review of pH and the associated terminology. Soil pH or soil reaction is an indication of the acidity or alkalinity of soil and is measured in pH units. The pH scale goes from 0 to 14 with pH 7 as the neutral point. As the amount of hydrogen ions in the soil increases, the soil pH decreases, thus becoming more acidic. From pH 7 to 0, the soil is increasingly more acidic, and from pH 7 to 14, the soil is increasingly more alkaline or basic.
Using a strict chemical definition, pH is the negative log of hydrogen (H+ ) activity in an aqueous solution. The point to remember from the chemical definition is that pH values are reported on a negative log scale. So, a 1 unit change in the pH value signifies a 10-fold change in the actual activity of H+, and the activity increases as the pH value decreases.
To put this into perspective, a soil pH of 6 has 10 times more hydrogen ions than a soil with a pH of 7, and a soil with a pH of 5 has 100 times more hydrogen ions than a soil with a pH of 7. Activity increases as the pH value decreases.
Agronomists generally use soil pH as measured in a 2:1 water-to-soil mixture as an index of a soil's acidity or alkalinity. In a soil test report, pH is often reported with descriptive modifier as shown in Table 1.
Nitrogen One of the key soil nutrients is nitrogen (N). Plants can take up N in the ammonium (NH4+) or nitrate (N03-) form. At pH's near neutral (pH 7), the microbial conversion of NH4+ to nitrate (nitrification) is rapid, and crops generally take up nitrate. In acid soils (pH < 6), nitrification is slow, and plants with the ability to take up NH4+ may have an advantage.
Soil pH also plays an important role in volatization losses. Ammonium in the soil solution exists in equilibrium with ammonia gas (NH3). The equilibrium is strongly pH dependent. The difference between NH3 and NH4+ is a H+. For example, if NH4+ were applied to a soil at pH 7, the equilibrium condition would be 99% NH4+ and 1% NH3. At pH 8, approximately 10% would exist as NH3.
This means that a fertilizer like urea (46-0-0) is generally subject to higher losses at higher pH. But it does not mean that losses at pH 7 will be 1% or less. The equilibrium is dynamic. As soon as a molecule of NH3 escapes the soil, a molecule of NH4+ converts to NH3 to maintain the equilibrium.
There are other factors such as soil moisture, temperature, texture and cation exchange capacity that can affect volatilization. So pH is not the whole story.
The important point to remember is that under conditions of low soil moisture or poor incorporation, volatilization loss can be considerable even at pH values as low as 5.5.
Soil pH is also an important factor in the N nutrition of legumes. The survival and activity of Rhizobium, the bacteria responsible for N fixation in association with legumes, declines as soil acidity increases. This is the particular concern when attempting to grow alfalfa on soils with pH below 6.
Phosphorus
The form and availability of soil phosphorus (P) is also highly pH dependent. Plants take up soluble P from the soil solution, but this pool tends to be extremely low, often less than 1 lb/ac.
The limited solubility of P relates to its tendency to form a wide range of stable minerals in soil. Under alkaline soil conditions, P fertilizers such as mono-ammonium phosphate (11-55-0) generally form more stable (less soluble) minerals through reactions with calcium (Ca).
Contrary to popular belief, the P in these Ca-P minerals will still contribute to crop P requirements. As plants remove P from the soil solution, the more soluble of the Ca-P minerals dissolve, and solution P levels are replenished. Greenhouse and field research has shown that over 90 per cent of the fertilizer P tied up this year in Ca-P minerals will still be available to crops in subsequent years.
The fate of added P in acidic soils is somewhat different as precipitation reactions occur with aluminum (A1) and iron (Fe). The tie-up of P in A1-P and Fe-P minerals under acidic conditions tends to be more permanent than in Ca-P minerals.
Potassium
The fixation of potassium (K) and entrapment at specific sites between clay layers tends to be lower under acid conditions. This situation is thought to be due to the presence of soluble aluminum that occupies the binding sites.
One would think that raising the pH through liming would increase fixation and reduce K availability; however, this is not the case, at least in the short term. Liming increases K availability, likely through the displacement of exchangeable K by Ca.
Sulfur
Sulfate (S042-) sulfur, the plant available form of S, is little affected by soil pH.
Micronutrients
The availability of the micronutrients manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), and boron (B) tend to decrease as soil pH increases. The exact mechanisms responsible for reducing availability differ for each nutrient, but can include formation of low solubility compounds, greater retention by soil colloids (clays and organic matter) and conversion of soluble forms to ions that plants cannot absorb.
Molybdenum (Mo) behaves counter to the trend described above. Plant availability is lower under acid conditions.
Conclusion
So, soil pH does play a role in nutrient availability. Should you be concerned on your farm? Be more aware than concerned. Keep the pH factor in mind when planning nutrient management programs. Also, keep historical records of soil pH in your fields. Soils tend to acidify over time, particularly when large applications of NH4+ based fertilizers are used or there is a high proportion of legumes in the rotation.
Recent years have shown the pH decline occurring more rapidly in continuously cropped, direct-seeded land. On the other hand, seepage of alkaline salts can raise the pH above the optimum range. So, a soil with an optimum pH today may be too acid or alkaline a decade from now, depending on producer land management.
Prepared by:
Ross H. McKenzie
Research Scientist - Soil Fertility/Crop Nutrition
Telephone: (403) 381-5842
ive asked and asked for this fact info to say soil dosent need to be ph`d. 4 or 5 threads in here now and im still waiting. so heres a bit for those that have the desire to learn
Soil pH | Nitrogen | Phosphorus | Potassium | Sulfur | Micronutrients Farmers frequently ask, "What effect does pH have on availability of nutrients in the soil?" There is no simple answer to this question, since the effects of pH are complex and vary with different nutrients. However, some broad generalizations are useful to keep in mind when making nutrient management decisions.
Soil pH
The first order of business is a quick review of pH and the associated terminology. Soil pH or soil reaction is an indication of the acidity or alkalinity of soil and is measured in pH units. The pH scale goes from 0 to 14 with pH 7 as the neutral point. As the amount of hydrogen ions in the soil increases, the soil pH decreases, thus becoming more acidic. From pH 7 to 0, the soil is increasingly more acidic, and from pH 7 to 14, the soil is increasingly more alkaline or basic.
Using a strict chemical definition, pH is the negative log of hydrogen (H+ ) activity in an aqueous solution. The point to remember from the chemical definition is that pH values are reported on a negative log scale. So, a 1 unit change in the pH value signifies a 10-fold change in the actual activity of H+, and the activity increases as the pH value decreases.
To put this into perspective, a soil pH of 6 has 10 times more hydrogen ions than a soil with a pH of 7, and a soil with a pH of 5 has 100 times more hydrogen ions than a soil with a pH of 7. Activity increases as the pH value decreases.
Agronomists generally use soil pH as measured in a 2:1 water-to-soil mixture as an index of a soil's acidity or alkalinity. In a soil test report, pH is often reported with descriptive modifier as shown in Table 1.
Nitrogen One of the key soil nutrients is nitrogen (N). Plants can take up N in the ammonium (NH4+) or nitrate (N03-) form. At pH's near neutral (pH 7), the microbial conversion of NH4+ to nitrate (nitrification) is rapid, and crops generally take up nitrate. In acid soils (pH < 6), nitrification is slow, and plants with the ability to take up NH4+ may have an advantage.
Soil pH also plays an important role in volatization losses. Ammonium in the soil solution exists in equilibrium with ammonia gas (NH3). The equilibrium is strongly pH dependent. The difference between NH3 and NH4+ is a H+. For example, if NH4+ were applied to a soil at pH 7, the equilibrium condition would be 99% NH4+ and 1% NH3. At pH 8, approximately 10% would exist as NH3.
This means that a fertilizer like urea (46-0-0) is generally subject to higher losses at higher pH. But it does not mean that losses at pH 7 will be 1% or less. The equilibrium is dynamic. As soon as a molecule of NH3 escapes the soil, a molecule of NH4+ converts to NH3 to maintain the equilibrium.
There are other factors such as soil moisture, temperature, texture and cation exchange capacity that can affect volatilization. So pH is not the whole story.
The important point to remember is that under conditions of low soil moisture or poor incorporation, volatilization loss can be considerable even at pH values as low as 5.5.
Soil pH is also an important factor in the N nutrition of legumes. The survival and activity of Rhizobium, the bacteria responsible for N fixation in association with legumes, declines as soil acidity increases. This is the particular concern when attempting to grow alfalfa on soils with pH below 6.
Phosphorus
The form and availability of soil phosphorus (P) is also highly pH dependent. Plants take up soluble P from the soil solution, but this pool tends to be extremely low, often less than 1 lb/ac.
The limited solubility of P relates to its tendency to form a wide range of stable minerals in soil. Under alkaline soil conditions, P fertilizers such as mono-ammonium phosphate (11-55-0) generally form more stable (less soluble) minerals through reactions with calcium (Ca).
Contrary to popular belief, the P in these Ca-P minerals will still contribute to crop P requirements. As plants remove P from the soil solution, the more soluble of the Ca-P minerals dissolve, and solution P levels are replenished. Greenhouse and field research has shown that over 90 per cent of the fertilizer P tied up this year in Ca-P minerals will still be available to crops in subsequent years.
The fate of added P in acidic soils is somewhat different as precipitation reactions occur with aluminum (A1) and iron (Fe). The tie-up of P in A1-P and Fe-P minerals under acidic conditions tends to be more permanent than in Ca-P minerals.
Potassium
The fixation of potassium (K) and entrapment at specific sites between clay layers tends to be lower under acid conditions. This situation is thought to be due to the presence of soluble aluminum that occupies the binding sites.
One would think that raising the pH through liming would increase fixation and reduce K availability; however, this is not the case, at least in the short term. Liming increases K availability, likely through the displacement of exchangeable K by Ca.
Sulfur
Sulfate (S042-) sulfur, the plant available form of S, is little affected by soil pH.
Micronutrients
The availability of the micronutrients manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), and boron (B) tend to decrease as soil pH increases. The exact mechanisms responsible for reducing availability differ for each nutrient, but can include formation of low solubility compounds, greater retention by soil colloids (clays and organic matter) and conversion of soluble forms to ions that plants cannot absorb.
Molybdenum (Mo) behaves counter to the trend described above. Plant availability is lower under acid conditions.
Conclusion
So, soil pH does play a role in nutrient availability. Should you be concerned on your farm? Be more aware than concerned. Keep the pH factor in mind when planning nutrient management programs. Also, keep historical records of soil pH in your fields. Soils tend to acidify over time, particularly when large applications of NH4+ based fertilizers are used or there is a high proportion of legumes in the rotation.
Recent years have shown the pH decline occurring more rapidly in continuously cropped, direct-seeded land. On the other hand, seepage of alkaline salts can raise the pH above the optimum range. So, a soil with an optimum pH today may be too acid or alkaline a decade from now, depending on producer land management.
Prepared by:
Ross H. McKenzie
Research Scientist - Soil Fertility/Crop Nutrition
Telephone: (403) 381-5842
Cannabisworks
Active Member
ice mud it dont matter what your using i can see you dont even know what is in nutes as you are using about 60% all the same and payin for sugar in water for nothing. you obvu=ios are just doin what saleman tell you in a store..no offence most do.
by the way your crop isnt organic
by the way your crop isnt organic
Cannabisworks
Active Member
maybe if you had used ph the stems on them week plant would be able to suport themselves due to the lack of calcium it had to strengthen cell walls. see now if youd ph it would have got the cal it was askin for and not been week stemmed. seem nugs 10x that size and dont lean over..on good stems
pickmybud
Member
Thanks for the posts Cannabis. That article speaks more about the PH of the soil though, rather than the PH of the nutrient solution going into it periodically. I have been trying to do a good bit of reading lately on soil's ability to buffer against change in PH. Soils with high Cation Exchange Capacity (CEC) has a better ability to maintain their PH than those who have lower CEC. Clay soils and soils with a high amount of Organic Matter have high CEC. So I would think that in the relatively short amount of time that it takes to grow MJ, a good organic mix with a high CEC would be able to keep a fairly stable PH level.
What I am still trying to do research on is the feeding of nutrient solutions without PH adjustment and how that interacts with both the soil and the plant. I have read from several people on these forums that they successfully feed with nutrients such as Earth Juice without adjusting the PH. The company that makes EJ swears that you don't have to adjust. Just mix and feed. Others insist this is bogus and that you absolutely should PH adjust (most people seem to do it by bubbling up a tea).
I am a newb so I have been doing a lot of reading, but it seems opinions are very diverse on the matter. I try to find as much "technical" data as possible that I can digest, rather than just relying upon forums.
Could you share a bit about your experiences, including what nutrients you use, how you adjust PH, soil mix, etc?
Thanks again.
What I am still trying to do research on is the feeding of nutrient solutions without PH adjustment and how that interacts with both the soil and the plant. I have read from several people on these forums that they successfully feed with nutrients such as Earth Juice without adjusting the PH. The company that makes EJ swears that you don't have to adjust. Just mix and feed. Others insist this is bogus and that you absolutely should PH adjust (most people seem to do it by bubbling up a tea).
I am a newb so I have been doing a lot of reading, but it seems opinions are very diverse on the matter. I try to find as much "technical" data as possible that I can digest, rather than just relying upon forums.
Could you share a bit about your experiences, including what nutrients you use, how you adjust PH, soil mix, etc?
Thanks again.
Cannabisworks
Active Member
if we can provide them with food set to a ph number that makes all the ellements in the nutrient available at the needed levels then th eplant or microbes wont need to owrk as hard to create the edible food for th eplant or do its processes in the medium. just like the food itself is meant to do. a plant cant uptake more than it needfs. thats been proven for years, so cant force feed it. so why do we use all these boosters and so on if the plant cant take more of it. just like humans using steroids and supplements. if they dont use it up or need it then they just poop it out and it has done nothing. but if we have the light power to make more photosynthesus and so on then the plants needs increase. so we make food processing easier fo them by using correct ph and N/P/K ratios so the lant can forcus more on other processes to use htis more or extra food.
sure we can grow without it to a point. most foods are made to ballance within a tollerable level. so they will get the food at one point or other. but not as easily or readily available for the best and most food transport possible. and this just increases the whole deal by more thc and everything that we want.
i just had 3 little test plants out all summer. no food. watered by me 1 time with no ph. nbo care. looked at them 3 times in 3 months. but yet was completely healthy and green looking, so yes we can rgow without ph. but it was a joke for yields and hight growth.
sure we can grow without it to a point. most foods are made to ballance within a tollerable level. so they will get the food at one point or other. but not as easily or readily available for the best and most food transport possible. and this just increases the whole deal by more thc and everything that we want.
i just had 3 little test plants out all summer. no food. watered by me 1 time with no ph. nbo care. looked at them 3 times in 3 months. but yet was completely healthy and green looking, so yes we can rgow without ph. but it was a joke for yields and hight growth.
Cannabisworks
Active Member
and ive used almost every nute out there over the years. done a few testings for nute co as well. dont always believe what you read on a label. there are verry few nute co that label fully and truthfully. and is full legal to doi that to a point. therre is a clause same as food industry or restraurants have that allows them to withold items in a mix as long as it wont harm the public nor environment. alot of it is the so called secret ingredients that makes each co nute a bit different.
for my ph adjusting food i mix all the salts first in the water. then the non salt forms. then stir or bubble for half hour. then adjust ph. then stir or bubble again for anothe rhalf hour. then recheck and adjust if needed. it takes a little time for all the molecules in this to bind and do what they do so dont feed right away. ph may or may not still shift once set. will depend on what is in your water source.
ive yet to need to adjust any ph as in using lime for my soils. most lime in them will last about 3 months to help buffer the shifts.
you also need to see that jhaving the ph move about on its own this way then one time it gets more k than n. and the more of certain ellements even further bl;ocks others from being taken in. it just makes the whole process that much harder for the plant....not impossible but harder and slower. and i think we all know what we get from making plants work harder than they need...lackin yield and potencies. not to the point of crap, but from results iver seen tested it is always less and weeker
for my ph adjusting food i mix all the salts first in the water. then the non salt forms. then stir or bubble for half hour. then adjust ph. then stir or bubble again for anothe rhalf hour. then recheck and adjust if needed. it takes a little time for all the molecules in this to bind and do what they do so dont feed right away. ph may or may not still shift once set. will depend on what is in your water source.
ive yet to need to adjust any ph as in using lime for my soils. most lime in them will last about 3 months to help buffer the shifts.
you also need to see that jhaving the ph move about on its own this way then one time it gets more k than n. and the more of certain ellements even further bl;ocks others from being taken in. it just makes the whole process that much harder for the plant....not impossible but harder and slower. and i think we all know what we get from making plants work harder than they need...lackin yield and potencies. not to the point of crap, but from results iver seen tested it is always less and weeker
TheOrganic
Well-Known Member
So you say My plant didn't have enough calcium. You seem to know a lot about ph'ing your nutes and the process. Why wouldnt my leaves show a calcium def.....
That plant was staked up from the get go and didn't get a lot of wind to strengthen because of tight space........Thats the only plant Ive ever had that fell over. I doubt because of lack of calcium there's just no way buddy.
So Humboldts Veg is the same as FFOF veg. Humboldt organic is all a joke and not organic?
That plant was staked up from the get go and didn't get a lot of wind to strengthen because of tight space........Thats the only plant Ive ever had that fell over. I doubt because of lack of calcium there's just no way buddy.
So Humboldts Veg is the same as FFOF veg. Humboldt organic is all a joke and not organic?
Cannabisworks
Active Member
was just a general commnet dood. i dont know anything about your grow or how much calcium you used. i meant more that cacuim builds cell walls and makes stronger stems.
humbolts veg and ffof???..your talking soil right fox farm ocean forest??...and other is a nutrient and you think i said that is the same foods???>
theres a diff between organci based and an organic was my point and that is organic based
humbolts veg and ffof???..your talking soil right fox farm ocean forest??...and other is a nutrient and you think i said that is the same foods???>
theres a diff between organci based and an organic was my point and that is organic based
slonez47
Active Member
Soiless mixes are closer to hydro and don't require the neutral PH that soil needs. I, along with a few of these folks don't bother with PH readings. I use RO soil and nutes. My girl is clean, green, and budding mean. We're just the exception to the rule though I'm sure. We probably just happen to live in a PH indifferent latitude. That or there may be more to the story.for those that dont understand food again in here and ph...and those nutes have ph already in the bottle to make it stable. it has to or there is no shelf life. and is only organic based as i already said most on the market are. derived from dont make it organic and all that stuff on humbolts says dervived from and final form is all same as a synthetic nute. read the label....lol all it needs a 17% organic content to get a stamp of organic or from omri., omri disent even test for the base entry/. there are diff classes within omri classifications. its a government money grab. anbd that i have first hand exp on dealing with omri
ive asked and asked for this fact info to say soil dosent need to be ph`d. 4 or 5 threads in here now and im still waiting. so heres a bit for those that have the desire to learn
Soil pH | Nitrogen | Phosphorus | Potassium | Sulfur | Micronutrients Farmers frequently ask, "What effect does pH have on availability of nutrients in the soil?" There is no simple answer to this question, since the effects of pH are complex and vary with different nutrients. However, some broad generalizations are useful to keep in mind when making nutrient management decisions.
Soil pH
The first order of business is a quick review of pH and the associated terminology. Soil pH or soil reaction is an indication of the acidity or alkalinity of soil and is measured in pH units. The pH scale goes from 0 to 14 with pH 7 as the neutral point. As the amount of hydrogen ions in the soil increases, the soil pH decreases, thus becoming more acidic. From pH 7 to 0, the soil is increasingly more acidic, and from pH 7 to 14, the soil is increasingly more alkaline or basic.
Using a strict chemical definition, pH is the negative log of hydrogen (H+ ) activity in an aqueous solution. The point to remember from the chemical definition is that pH values are reported on a negative log scale. So, a 1 unit change in the pH value signifies a 10-fold change in the actual activity of H+, and the activity increases as the pH value decreases.
To put this into perspective, a soil pH of 6 has 10 times more hydrogen ions than a soil with a pH of 7, and a soil with a pH of 5 has 100 times more hydrogen ions than a soil with a pH of 7. Activity increases as the pH value decreases.
Agronomists generally use soil pH as measured in a 2:1 water-to-soil mixture as an index of a soil's acidity or alkalinity. In a soil test report, pH is often reported with descriptive modifier as shown in Table 1.
Nitrogen One of the key soil nutrients is nitrogen (N). Plants can take up N in the ammonium (NH4+) or nitrate (N03-) form. At pH's near neutral (pH 7), the microbial conversion of NH4+ to nitrate (nitrification) is rapid, and crops generally take up nitrate. In acid soils (pH < 6), nitrification is slow, and plants with the ability to take up NH4+ may have an advantage.
Soil pH also plays an important role in volatization losses. Ammonium in the soil solution exists in equilibrium with ammonia gas (NH3). The equilibrium is strongly pH dependent. The difference between NH3 and NH4+ is a H+. For example, if NH4+ were applied to a soil at pH 7, the equilibrium condition would be 99% NH4+ and 1% NH3. At pH 8, approximately 10% would exist as NH3.
This means that a fertilizer like urea (46-0-0) is generally subject to higher losses at higher pH. But it does not mean that losses at pH 7 will be 1% or less. The equilibrium is dynamic. As soon as a molecule of NH3 escapes the soil, a molecule of NH4+ converts to NH3 to maintain the equilibrium.
There are other factors such as soil moisture, temperature, texture and cation exchange capacity that can affect volatilization. So pH is not the whole story.
The important point to remember is that under conditions of low soil moisture or poor incorporation, volatilization loss can be considerable even at pH values as low as 5.5.
Soil pH is also an important factor in the N nutrition of legumes. The survival and activity of Rhizobium, the bacteria responsible for N fixation in association with legumes, declines as soil acidity increases. This is the particular concern when attempting to grow alfalfa on soils with pH below 6.
Phosphorus
The form and availability of soil phosphorus (P) is also highly pH dependent. Plants take up soluble P from the soil solution, but this pool tends to be extremely low, often less than 1 lb/ac.
The limited solubility of P relates to its tendency to form a wide range of stable minerals in soil. Under alkaline soil conditions, P fertilizers such as mono-ammonium phosphate (11-55-0) generally form more stable (less soluble) minerals through reactions with calcium (Ca).
Contrary to popular belief, the P in these Ca-P minerals will still contribute to crop P requirements. As plants remove P from the soil solution, the more soluble of the Ca-P minerals dissolve, and solution P levels are replenished. Greenhouse and field research has shown that over 90 per cent of the fertilizer P tied up this year in Ca-P minerals will still be available to crops in subsequent years.
The fate of added P in acidic soils is somewhat different as precipitation reactions occur with aluminum (A1) and iron (Fe). The tie-up of P in A1-P and Fe-P minerals under acidic conditions tends to be more permanent than in Ca-P minerals.
Potassium
The fixation of potassium (K) and entrapment at specific sites between clay layers tends to be lower under acid conditions. This situation is thought to be due to the presence of soluble aluminum that occupies the binding sites.
One would think that raising the pH through liming would increase fixation and reduce K availability; however, this is not the case, at least in the short term. Liming increases K availability, likely through the displacement of exchangeable K by Ca.
Sulfur
Sulfate (S042-) sulfur, the plant available form of S, is little affected by soil pH.
Micronutrients
The availability of the micronutrients manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), and boron (B) tend to decrease as soil pH increases. The exact mechanisms responsible for reducing availability differ for each nutrient, but can include formation of low solubility compounds, greater retention by soil colloids (clays and organic matter) and conversion of soluble forms to ions that plants cannot absorb.
Molybdenum (Mo) behaves counter to the trend described above. Plant availability is lower under acid conditions.
Conclusion
So, soil pH does play a role in nutrient availability. Should you be concerned on your farm? Be more aware than concerned. Keep the pH factor in mind when planning nutrient management programs. Also, keep historical records of soil pH in your fields. Soils tend to acidify over time, particularly when large applications of NH4+ based fertilizers are used or there is a high proportion of legumes in the rotation.
Recent years have shown the pH decline occurring more rapidly in continuously cropped, direct-seeded land. On the other hand, seepage of alkaline salts can raise the pH above the optimum range. So, a soil with an optimum pH today may be too acid or alkaline a decade from now, depending on producer land management.
Prepared by:
Ross H. McKenzie
Research Scientist - Soil Fertility/Crop Nutrition
Telephone: (403) 381-5842
slonez47
Active Member
I had the same exact worries my friend. I'm using RO soil and nutes. When I PHed the nutes I freaked because it was damn near red. After long discussion I tried the nute mix without PHing the mix, and have'nt looked back. I tried it on one plant and you can, or not. It works for me dude. I sweated about pouring acid on my girl, but the soil, or the bennies, or living half assed right worked. My MK is fucking awesome.
slonez47
Active Member
Feed the soil and your plant will be happy.