Soil Test Results on Compost

Ozark · February 5, 2019

Three years ago I asked the electric company tree trimmers to dump wood chips on my property. They left me a mountain of them and I did nothing further to compost the chips. I got the chips in the summer, so there were a lot of green leaves included which I know helped break the wood down.

Now, deep in the pile I've got what looks and smells like the best black soil ever. I dug into it last week and sent off a soil sample to our University Extension. Got the results back today and I'm very happy with it, but I have some questions. The acidity seems a bit alkaline for veggies, and the minerals are high as well. I'm building raised beds for a new garden; tomatoes, peppers, squash, beans, okra, etc. Should I fill the raised beds with this compost alone, or should I mix it with topsoil or something else that's a little more neutral? What do you think?

Here's the soil report:

"pHs 7.5 (high), Phosphorus 512 lbs/ac (excess), Potassium 1779 lbs/ac (excess), Calcium 13380 lbs/ac (high), Magnesium 1088 lbs/ac (high), Organic Matter 44.4%" (Note, I don't know where they got that - it's 100% organic compost!).

These numbers make the compost seem VERY rich, and I'd be concerned if it were not for this written summary at the bottom of the soil report:

"Your soil test report reveals a soil that is nutritionally well suited for vegetable production. No nutrients other than nitrogen are needed at this time. Nitrogen fertilization rates and timing are determined by the specific vegetable crop. I recommend retesting your garden soil in 2-3 years."

So - maybe "excess" Phosphorus and Potassium don't hurt, and a pH of 7.5 is OK also? The lab says it's OK and I'd really prefer to use it straight - what do you think? Thanks!

February 5, 2019	#1
Ozark Tomatovillian™ Join Date: Jan 2008 Location: Ozark, Mo. Posts: 201	Soil Test Results on Compost Three years ago I asked the electric company tree trimmers to dump wood chips on my property. They left me a mountain of them and I did nothing further to compost the chips. I got the chips in the summer, so there were a lot of green leaves included which I know helped break the wood down. Now, deep in the pile I've got what looks and smells like the best black soil ever. I dug into it last week and sent off a soil sample to our University Extension. Got the results back today and I'm very happy with it, but I have some questions. The acidity seems a bit alkaline for veggies, and the minerals are high as well. I'm building raised beds for a new garden; tomatoes, peppers, squash, beans, okra, etc. Should I fill the raised beds with this compost alone, or should I mix it with topsoil or something else that's a little more neutral? What do you think? Here's the soil report: *"pHs 7.5 (high), Phosphorus 512 lbs/ac (excess), Potassium 1779 lbs/ac (excess), Calcium 13380 lbs/ac (high), Magnesium 1088 lbs/ac (high), Organic Matter 44.4%"* (Note, I don't know where they got that - it's 100% organic compost!). These numbers make the compost seem VERY rich, and I'd be concerned if it were not for this written summary at the bottom of the soil report: "Your soil test report reveals a soil that is nutritionally well suited for vegetable production. No nutrients other than nitrogen are needed at this time. Nitrogen fertilization rates and timing are determined by the specific vegetable crop. I recommend retesting your garden soil in 2-3 years." So - maybe "excess" Phosphorus and Potassium don't hurt, and a pH of 7.5 is OK also? The lab says it's OK and I'd really prefer to use it straight - what do you think? Thanks!