Here is a short blog on “How to fix High pH soil”One of my favorite things to talk about is how to fix high-pH soil. many of us are dealing with high-pH soils. And over the years we have heard of, “Oh there’s nothing I can do with my high pH soil “.
You absolutely can fix that if you want to. We’ll talk a little bit about what we’ve done in our operation and what we’ve helped other farmers with as well to get that pH down.
Obviously when we talk about fixing a high pH soil and you say, “Well man I’m going to invest some money in that ground, I’m already getting good yields why do that?” Well, take a look at what you’re getting for yields, do you think you could do better?
I talked to a farmer who had 200-bushel corn and 60-bushel soybeans in North Dakota and he said, “I don’t have any problem at all, I’m getting the highest yields around me.” And I said, “Well how high do you think your yields could be if your pH wasn’t hurting you?” He was like, “How exactly is my pH hurting me?” That’s a great question.
When we look at our soils and we see pHs that get even above 7 all of a sudden our micronutrient availability starts going down, our phosphorus availability goes down, our calcium availability goes down and we start having issues getting those nutrients and sufficient quantities into our plants.
when our plants are in a high demand period this problem becomes exaggerated. They need those nutrients quickly and they just can’t get them.
let’s keep in mind different crops can tolerate different soil pHs. So on the high side of things, barley can do fairly well. Alfalfa likes a pH right around 7. There are a lot of crops that can survive that, sugar beets I can think of. So on the flip side, blueberries, for example, they like a pH down around 5 or 5.5 or something like that. So it depends a little bit on what crop you are raising and which soils that particular crop likes.
But let’s put it this way, for corn, soybeans, and wheat the 3 major acreage crops in the United States those crops like a pH of around 6.3 to 6.8 so that’s kind of what we’re shooting for.
Reason for High pH in soil
So if you want to drop your pH you first have to ask yourself, “Why did my pH get high in the first place?” Now could it be that it’s poor drainage? That’s what we see very commonly.
When drainage is poor you usually have a build-up of salts over time and eventually, your pH goes up. Ok, so you can fix that drainage problem.
You also may have something like soil erosion where all your topsoil is gone and now you’re farming the subsoil and your subsoil may have started with a whole bunch of calcium or lime in it and the pH was a little bit elevated. So there are several reasons why your pH could be high.
How to fix High pH soil
Fix Poor Drainage
but the first thing we always talk about is to make sure we have good drainage because what we want to do is flush things out of that soil. For example, magnesium can raise soil pH by roughly 1.6 to 1 compared to calcium.
Sodium can raise pH roughly 4 to 1 compared to calcium. So I want to flush out the salts, I want to flush out the sodium, I want to flush out the magnesium if those things are in excess- I can’t do that if I have poor drainage.
You know one thing I’d say is fixing that drainage is not the silver bullet that all of a sudden tomorrow your pH is going to drop from 8 to 6.5 that’s not going to happen. It’s going to be a slow process that’s going to happen over time, but it’s going to enable that process to happen. The next thing that you’re going to have to do is make some changes to your soil program. How to Grow Banana Trees from Banana
One might be elemental sulfur. At the Ag PhD Field Day once again this year we were doing some work with elemental sulfur on well-drained soils to try to move pH down. Now in the case at the Field Day, we didn’t have a pH over 8 but we did have a pH in the low to mid 7s that we were able to bring down in one season down into the 5s with enough elemental sulfur.
Now we didn’t want the pH down into the 5s but we did some experiments just to show, “Hey let’s put on enough and see if we can move it down, that way we can dial in what our rate needs to be.” And like all these things that we talk about here, you can say well I’m not going to turn my whole 2,000-acre farm to this program immediately.
That’s fine, try one field. See what a difference it can make. Improve the drainage in one field, and try some elemental sulfur if that’s the right recipe that you and your agronomist work out for you hey this will help solve my problem. Try it in one field, see what happens over a couple of years and when you learn lessons that can be applied to the rest of the farm you’re going to make more money.
Alright, so you have to ask yourself again, why is this pH bad, nevertheless you want to make sure you have good drainage out there. So that means tile that means getting your calcium levels up above 65% and the base saturation number maybe even above 70%.
You’ve got to have good calcium so you have better soil porosity. The elemental sulfur one of the things that can do is the sulfur can bind together with magnesium it can bind together with sodium then it’s going to form salts and those salts are leachable. Salts can leach through that soil with normal rainfall again as long as you have good drainage.
So that’s part of the reason the pH goes down, but yes you want to have elemental sulfur out there, not gypsum but elemental sulfur because what happens is when that conversion occurs from sulfur over to sulfate you’re going to have sulfuric acid produced, and that sulfuric acid is going to lower that pH.
So a lot of people ask, “Is elemental sulfur going to fix my soil pH for the long term?” it will if you’ve taken care of the other problem.
So if you’ve got your magnesium down, your sodium down, your salts are down. Then yeah it’s very likely that that elemental sulfur can cure your pH once and for all and when that high pH is gone so goes your iron deficiency chlorosis issue, so goes a lot of your micronutrient issues and your tie-up with phosphorus and some of those other nutrients.
So getting the pH down can be a really good thing for your farm. The big thing is when you look online if you see one experiment with elemental sulfur or one experiment with drainage well that one thing isn’t going to solve it, it’s a combination approach as we discussed today.