Question 1

How often should I soil test?

Accepted Answer

Test every 2-3 years for most fields. Test annually if you're making major changes to your fertility program or experiencing yield problems.

Question 2

What do the NPK numbers mean?

Accepted Answer

NPK numbers on fertilizer bags show the percentage of nitrogen (N), phosphorus (P2O5), and potassium (K2O). A 10-20-10 fertilizer contains 10% N, 20% P2O5, and 10% K2O by weight.

Question 3

Should I apply all nitrogen at once?

Accepted Answer

For most crops, split applications are more efficient. Apply 30-50% at planting and the remainder as sidedress when the crop can use it. This reduces losses to leaching and volatilization.

Question 4

Do soybeans need nitrogen fertilizer?

Accepted Answer

Generally no - soybeans fix their own nitrogen through root nodule bacteria. However, they do need adequate P and K. In some cases, a small starter N application (20-30 lbs) may help early growth.

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