Using pH up to raise soil ph

Apical Bud

Well-Known Member
Hi everyone. A friend of mine has an acidic soil (5.4). We are having a discussion about how to raise it quickly. We would like to use a pH up, which is composed of calcium carbonate, and flush with 8.2 water. Is this an acceptable idea? We have discussed using fine dolomite lime but we feel that we'd have to add so much to adjust the pH above six that we'd end up with a salinity problem.
Any ideas on these two options? Any other suggestions for raising pH quickly? (If one can even raise pH quickly)

He is growing in a 25% coco + rich compost and perlite. The soil pH after a 24 hour soak is 5.5, and the run off from a recent flush is 5.4.

Thanks every one, this should be a quick an dirty thread.
 

justugh

Well-Known Member
Hi everyone. A friend of mine has an acidic soil (5.4). We are having a discussion about how to raise it quickly. We would like to use a pH up, which is composed of calcium carbonate, and flush with 8.2 water. Is this an acceptable idea? We have discussed using fine dolomite lime but we feel that we'd have to add so much to adjust the pH above six that we'd end up with a salinity problem.
Any ideas on these two options? Any other suggestions for raising pH quickly? (If one can even raise pH quickly)

He is growing in a 25% coco + rich compost and perlite. The soil pH after a 24 hour soak is 5.5, and the run off from a recent flush is 5.4.

Thanks every one, this should be a quick an dirty thread.
what u are talking about is a quick fix .........from the sound of it he has bigger issue

1 what is the ph of the water he is using .......city water or well water
2 the soil sounds like needs to be reworked
2a http://www.amazon.com/gp/product/B00OEEGCHS
the lime is the right idea but since u got to work it might as well cover base and add in some stuff plant needs to make resin for us
2b http://www.amazon.com/gp/product/B003STB5N6
the hero to all soil growers (be generous with them )

those 2 things and 2 weeks of a quick cook method the soil should be stable and ready to go for planting
if the guy is city water then he needs a carbon filter to scrub out the chemicals they add to water
http://www.amazon.com/gp/product/B007I6MN72
if his water PH is low naturally .......he needs to use some compost tea /organic feed sup up the micros in the soil to keep it phed for him

what u are asking about is Flushing the soil
that will correct the imbalance for a short time but what ever is causing it will just do it again u need to get ahead of it to keep from happening to stop it other wise will be doing it every other week
 

Apical Bud

Well-Known Member
justugh, thanks for your reply. He uses an ro filter but his water comes in at 7.5. It is easily neutrilized. There definitely is a larger problem. He has plants in 10 gallon pots but usually waters with about a half gallon. He pHs his water to 6.4 every time he feeds. He uses a nute line that claims it should be used every watering, and so he does. He hasn't watered enough to produce run off for over two months. His run off ppm is 2000+ and pH is low. The nutrient line he uses is almost all phosphorus, with a few amendments having some potassium and a little nitrogen.
We both agree that he has caused a fert build up and we are assuming it is responsible for the pH problem and the salinity because the base soil comes in at 7.0.
Our disagreement is about pH adjustment. He says he has tried balancing acidic soil before by watering with 8.0, ph-up-ed water (which I believe is too weaksauce to do anything to the soil) and had bad results, so he is hesitant to adjust that way, but I believe that is the only short term fix, as lime in fine powder will quickly bring the ph above his feared 8.0 mark and large grain lime will take too long to affect the pH.

But it sounds like you're saying watering with alkaline solution to affect acid soil is doable and won't cause more problems than it will fix?

Also I am interested in compost tea for soil stability. But if I'm not mistaken relying on rhizosphere biomass is a long term rather than a short term solution, right?
 
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Apical Bud

Well-Known Member
I just want to know if watering let's say a 5.5 soil with 8.5 water will correct pH issues in the short term. Any one know?
 

Resinhound

Well-Known Member
How are you finding.the soil ph? Runoff isnt an accurate indicator.You are flushing built up salts from the soil..those will give you a low ph reading.If you want to fix that get your runoff PPMS back down into a realistic level and the ph should come up with it.If its still low,which I doubt it will be, a small amount of garden lime can be watered in.And lastly he needs to get a realistic nutrient program going.Mostly phosphorus with a little potassium and nitrogen thrown in isnt a good way to grow healthy plants.
 

Apical Bud

Well-Known Member
How are you finding.the soil ph? Runoff isnt an accurate indicator.You are flushing built up salts from the soil..those will give you a low ph reading.If you want to fix that get your runoff PPMS back down into a realistic level and the ph should come up with it.If its still low,which I doubt it will be, a small amount of garden lime can be watered in.And lastly he needs to get a realistic nutrient program going.Mostly phosphorus with a little potassium and nitrogen thrown in isnt a good way to grow healthy plants.
Hey thanks for your reply! I took half a cup of soil from the root zone about two weeks ago and added half a cup of water to it so that it formed a mud. I let the mud sit for 24 hours then added a quarter cup of di water and read the pH. It came in at 5.3. Then a week later I put 3 gallonsof di water into the plant, which was in a 10 gallon 25% Coco soil, adding a liter at a time for about an hour. After the hour, and once water had begun to drip from the bottom, collected the first cup or two in a clean bin. That is what gave me my ppm reading.

An update. After "flushing" ( 500 gallons of water in 480 gallons of soil, which I know isn't really a full flush) the run off was still 1500 ppm and the pH off the concentrated run off was 5.7. But, after 5 days of not touching the soil, run off from the next watering was 6.5 and the ppm 500.
I don't understand this. My procedure for taking the run off was similar. We had actually watered with a fertilizer at 600 ppm (which I told him not to do) at pH 7.
Does this make any sense? The ppm should have been similar to the last run off, right? Did the five days post flush allow salts to equilibrate pH? Has anyone experienced a similar phenomenon?

I should also add that we have some heavy microbial activity. We have been adding composting microbe mixes and our soil is freshly composted (it arrived hot, around 130 f). We have beautiful yellow mushrooms popping up everywhere. We have had a discussion about fungus out competing our roots, or possibly eating our nutes and lowering pH.
 
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Papa OG

Member
I know this is a little old but I have some info to help. Although compost teas are great for microbial action and general soil health, the byproduct of this action can create acidity. I'm not sure which microbes were involved because there are many but the excess of salts (food) caused a bloom and net decrease in ph. When you flushed the salts, the microbes went with. This leaves the residual Colonies to pick up the slack and begin again.

If you are using soil, you already have microbes available for the job and unless you flood the soil with salts (nutrients), you should have fairly tolerable ph holding.

I'm not saying that you shouldn't use microbial boosters, but make sure you know the process you are initiating. Once it begins you will know how to work with it or fix it.
 
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