Originally Posted by PureHarvest
Let me chime in here with some general thoughts, then some more specific.
pH is not something you goal-seek. You balance ALL your elements based on your soil type and the pH will go where it needs to go.
Trying to change pH without regard to all the other factors is like trying to change your temperature without asking what is causing your temperature to be high or low.
You might get a reading of 102 and take an aspirin to get it lower, but you never took the nail out of your foot that you accidentally shot out of your nail gun last week.
Base saturation tells us what the soil is composed of in terms of the cations: calcium, magnesium, potassium, and sodium.
The ideal is for calcium and magnesium to equal 80%.
In a heavy clay, calcium should be about 70% and magnesium 10%. Yours is 60 and 7.7.
A sandy soil would need 60 cal and 20 mag.
Calcium opens up the soil, and magnesium tightens it up and makes it sticky. It grabs the water available.
So, now would be a good time to mention that you can over apply ANY material/element with harmful results.
The soil can only hold so much stuff. When you put too much of one thing, something else has to be pushed off to make room.
Now, based on your test, you absolutely should not just put down calcium lime. You want Dolomitic lime, as it provides magnesium along with the calcium (you need to raise both elements).
Your potassium is also low. It should be 3 to 5%. You are .81
So, yes, calcium will raise pH, but so will magnesium and potassium.
So you want to ask, why am I raising my pH, and how. By adding the mag and potassium you need, your pH will inherently go up.
Another way to put it is when someone says to me, "my pH is 5.8", my first question is "WHY"? Then we add what is missing, and it goes where it should for your soil type.
Hopefully your sample was not from a spot that has had sulfur put on it in the last 6 months (could be sulfur coated urea, or ammonium sulfate form of nitrogen), or just a moderate to heavy app of nitrogen in the last 30 days. This can drop the pH and make it seem as though you need calcium.
|