Asked July 31, 2015, 10:17 AM EDT
I have an empty garden that I plan to use as a vegetable garden next year. I got a soil test for it. I have figured out how much NPK fertilizer I need to apply.
I plan to improve the soil this fall by adding compost, manure, coffee grounds, peat moss, and some sulfur. (The pH is 7.8, and the soil is sandy – thus the peat moss and sulfur.)
I know that nitrogen dissipates into the atmosphere, so I will be adding that in the spring before I plant, and again in later summer if needed.
My question is about the P and K: Can I add the bone meal and potash in the autumn when I plan to add the compost, etc., or should I wait until spring? Will it leach out of the soil with no plants present, or is it better to add in the fall and kind of let it “soak in” to the soil over the winter? Also, just to verify – I was informed that the sulfur takes time to react to the soil, so it is good to add a season ahead of time. Is that correct?
Livingston County Michigan
While it does take time to increase the organic matter and change the pH of your soil, fertilizing is most effective when done prior to planting (or after planting with care taken not to burn the plants). I suggest you wait until spring to add the bone meal and potash when you fertilize with nitrogen. This will give your veggies a good source of nutrients to take up as they get started growing.
Click on this link to an article with a great deal of information about nutrients and soil pH: Fertilizing Garden and Landscape Plants and Lawns