This link may help...

Here is a link that might be useful: Changing soil PH

o Stop adding sand to clay.
o Stop with the ash.
o You can't lower pH in your time frame without side effects; the link above fails to discuss the possible risks of too much Al2(SO4) addition. Judging from the info provided above, I'd be very hesitant in recommending that amendment for the OP. I'd instead recommend adding sulfur and living with the consequences.
o Not knowing the analysis prior to amendments, I wonder if the manure was fully composted, and whether the 2 tons was added to, say, 400 sf (meaning too much).

Good luck.

Dan

I agree with Dan. Sulfur is the best way to go IMO.

Concur. Most vegetables have a pretty wide tolerance to a range of pH. some like beets, spinach and limas actually prefer a higher pH. Also if the pH elevation is due to the wood ash, it will be temporary. Potassium Hydroxide (the main pH changing ingredient in wood ash) is relatively soluble and will react quickly. If you have naturally alkaline soil than sulphur is the way to go.

Just curious, how did you take your soil sample (please be specific) and how deep did you incorporate the composted dung?

I doubt that the wood ash alone is reponsible for high pH.
How much wood ash to how big/small an area did you add?
Maybe the horse manure did it, as you mentioned adding tons of it ?!. It is not the manure itself, but what the use to prevent smell, etc around the horses.
But at any rate, you should follow the advices of the experts to lower the pH. As farmerdill mentioned, most garden veggies have a wide pH tolerance range but slightly acid soin(pH less than 7) is preferable.
HIGH PHOSPHORUSTypical scenario. This means that for fertilizing, in most cases, all you need is Nitrogen. P and K stick around for a long time in the soil.

OK. Let me answer a few questions, and please forgive me if I forget something.

The manure that I added was composted cow manure that had been composted for at least 2 years since it became a by product of the animal. The gentleman I purchased the compost from also owns a landscape nursery and taught horticulture on the college level for several years prior to retiring. The manure looked no differently than black dirt when I incorporated it into the soil.

The garden area that I am concerned with is approximately 40 feet wide by 60 feet long. I till to a depth of 18 inches every spring and fall.

The soil sample was taken by using a 2 inch pvc pipe. I tapped the pipe down to 18 inches in 20 different areas. Then, I emptied each 'plug' into a 5 gallon bucket, and mixed everything very well before taking 4 cups of the soil to the local Agricultural Extension Office for testing.

As for the wood ash ....
I burned several large rounds of oak in each of 6 piles throughout the garden prior to last falls till.

Please comment.

I cant give you any advice other than the local extension office here has been very helpful with the questions I have. Every county should have one. It should be in your phone book under county offices then down to extension office. I would give them a call. They used to make house calls free.

Few Co Extensions make house calls any more, we don't give them money to help people. They can answer calls or e-mails.

First thing is we don't know where you are and we don't know your soil type, both of which are important.

So depending upon how much manure has been added in the past, you might be done for several years on the large-scale additions. It doesn't say what your OM % is, but you can easily do that at home. Over, say, 7-9% and any more addition of manure will keep jacking up your P-K and you don't need that; maybe this fall just straight leaf compost if anything. You can go to a nursery or feed supply and get soil sulfur and it will have a chart telling you how much to apply to get so much reduction. Depending upon your soil type and soil temp and critter activity, you may see some reduction mid-summer but likely end-of-summer. This may be an operation to be done more than once.

Since your pH didn't go up in a day, you can't reduce it in a day either (I've tried to get that entered into our national discourse, but I digress). You'll have to deal with your soil now and some crops will be unhappy. But we play the hand we're dealt. Happy gardening. I wish I had that much space!

Dan

Dan has good suggestions, and besides his suggestions I think you should go with leaves and urea only for a couple of years at least. Urea to be added based on how green plants are. If they are very green, nothing. Two tons of manure are about 40 lbs of nitrogen, which is a lot for any garden, and the typical decay time is one year, so no N this year, and play it by year the next.

but let me mention that it is unlikely that your high pH is due solely to wood ash. You would have had to burn cords and cords to get from, say, 6.5 to 7.6. The way you describe your situation, you just clear-burned the area.

but let me mention that it is unlikely that your high pH is due solely to wood ash.

I'm wondering where it came from too, which is why I asked the location for clues. I'd also use leaching from snowmelt to help, meaning additions in fall. Maybe a cover crop too for spring incorporation...

Dan

Interesting idea for a soil sampling probe! Did you sharpen the end at all or leave it a square cut? I'll suppose you got good cores but it might not be that important as you have been stirring up the soil each year to rooting depth and more so getting really good, representative cores from 0 - 18" wouldn't really be important.

Ditto on the Sulfur for lowering pH, it can come wholly from ag. sulfur and some can also come from ammonium sulfate, a common N fertilizer in some places.

As I think was mentioned elsewhere, the pH lowering effect of S is not immediate in soil. In very simple terms, the S is acted on by soil microorganisms that convert it to sulfuric acid which itself drops the pH. The conversion of S to sulfuric conversion is temperature and moisture dependent, too cold and/or dry and it can slow to a crawl and then stop.

Manures can raise the pH of soils because they contain salts. I suspect your very high potassium and phosphorus readings reflect the ash addition you made. I have read conflicting data suggesting it may take years for the effects of ash addition to right itself. So right off the get-go you have had a double whammy with the manure and ash. If you have clay soil, that is also commonly associated with high pH. High water tables can even affect the pH of your soil.

Like suggested, lay off the ash and animal manure and going with green manures instead. I commend you for getting a sample done, but it should be done before you ammend ;-)

How's the drainage?

What is your native pH? The information given looks like your soil is a western soil with a lot of added manure. I would expect it to be lower in your area, but it could normally be in that range based on the parent materials for your soil (limestone based soils will naturally have high calcium and higher pH's). My soil runs from 7.7 to 8 for pH. Never noticed that it caused a problem with the garden, although some other things like raspberries will show signs of iron deficiency. I tried to lower my pH once, adding lots of sulphur, and had pretty much no response. I also added lots of organic matter and brought the content up from 1% to around 5% organic matter. This had the best effect on pH, lowering the garden from 7.9 to 7.7. So, if you don't lower the pH, it really shouldn't be a big problem for the garden. Lowering the pH could take some time given how much calcium is present in your soil--it will take a lot of acidifying to neutralize the calcium.

The high P and K can occur with large additions of rotted manure. The rotted manure is also relatively low in nitrogen and you could find yourself needing to add nitrogen in mid-summer. Watch the lower leaves on your corn for signs of nitrogen deficiency and add nitrogen as soon as symptoms develop.

With the high P and K and Zinc, other mineral nutrients may be quite high also. This can result in symptoms of deficiency, such as zinc deficiency, not because it is too low in the soil, but other excess nutrients block its uptake by the plants. Not a prediction, just something to watch out for.

Finally, manure can contain a lot of salt. If the soil drains well, this will leach out with excess rainfall or irrigation, but you could see some salt problems develop this year. For me, this has happened first in beans and peas with everything else more tolerant. I layed off the manure for a couple years and my salt content came down nicely.

Although I agree with many of the replies given thus far I'd hesitate to follow any recommendations from an improperly taken soil sample. What promped you to sample that deeply? Do yo routinely work the soil to that 18" depth?

There is probably little doubt that you will encounter some problems with certain crops in that plot. If it is less than a tenth acre I'd go out and buy 20 bales of spagnum peat moss/2400(40'x60') sq ft and work it well into the top 7-8" of topsoil only. Then plant a few tomatoes or other crops that might tolerate a wider pH range. Avoid cucurbits on a large scale until you can see the response that they might have on a small scale.

I'd hold off on any fertilizer, including nitrogen, until a little later this summer. When you resample your soil don't test beyond 8" depth.

The reason I took the soil sample to 18" is because that is my till depth.

The soil's native pH is around 8 to 8.2 . The native composition is an Alluvial clay composition.

I spoke to my local Ag representative today, and she mentioned that I should try ammonium sulphate at a rate of 4 pounds at this time. Then, I will take a mid-season soil sample to see if the problem is being corrected by the ammonium sulphate. My main concern, at this time, is that in using too much ammonium sulphate I will be adding more nitrogen to an already nitrogen rich soil. This would result in over vining, and in the worst case, nitrogen burn.

Could herbicide overuse be a contributor to my problem? 20+ years ago my property was a farm field. Could their be any residual herbicide that would cause my pH to remain high ... ie : salts resulting from pesticide use?

My main concern, at this time, is that in using too much ammonium sulphate I will be adding more nitrogen to an already nitrogen rich soil.

That was several of our concerns upthread as well.

Could their be any residual herbicide that would cause my pH to remain high ... ie : salts resulting from pesticide use?

Doubtful. pH is mostly from parent material. Maybe a couple tenths from the amendments.

beeone is more explicit that I was upthread, so I'll repeat: you may want to amend in the fall for a few seasons so the leaching happens and the soil critters get time to work.

Dan

Is that 4 lb. Amm. Sulphate per 100 sq. ft? That might be a relatively safe rate but it is doubtful that it will modify your pH very much in the short term.

In reality soil recommendations are made based on 2 million lb. soil per acre which is usually calculated at 6 2/3" plow depth. Anything that you work into 18" depth is therefore diluted by three times.

I stand by my earlier peat recommendation. I add that amount to a 30x96 greenhouse soil annually and I need to also annually add limestone to keep my pH from sinking too low. You should be able to get it at $9-10 per 3.8 cu.ft. bale. Eventually your high organic matter from the manure breaking down might help to lower pH a little too. I'll agree with Dan that any pesticide use is insignificant to pH. If there is herbicide residue you will have other problems out of your control to deal with other than plant a similar crop that preceeded your working the soil.

I fill out an info sheet when I submit my soil sample to my county Ag. extension agent to be sent in to KSU for testing. On that form I check off all my anticipated, desired crops, list any disease or pest problems, and describe my fertilizing, amending, and soil supplementing practices.

I usually describe how often I dump lawn clippings and leaves in the garden, and answer that I make amendments and supplement the soil as per their recommendations and tell them that I typically use only urea fertilizer in quantities they suggest.

I then always ask that they recommend a fertilizer and amendment plan for the year, both before planting and as side-dressing.

This year, they advised me to apply a certain amount of sulfur to lower the PH (though it was 7.0, and used to be a lot higher before they started having me add it about every other year). They said I had high P & K levels, and should keep on using only high N fertilizer. None was needed before planting, but they gave me a sheet containing complete timing and amounts for side-dressing.

Very helpful, inexpensive, and more comprehensive than you can get by asking here. Though the people here are helpful and friendly, most probably have no idea where you even live.