More Compost Might Not Be What Garden Soil Needs

MSU News Service

With spring arriving, gardeners are preparing soils for this year’s planting, and many love to apply compost, which can supply nutrients, feed microbial activity, help retain soil moisture and improve soil structure.

However, there can be too much of a good thing, according to Clain Jones, Montana State University Extension soil fertility specialist and professor in the MSU Department of Land Resources and Environmental Sciences. “I have been receiving many soil tests from vegetable gardens with excessively high levels of nitrogen, phosphorus and potassium,” Jones said. “The owners are asking what can be done to remedy the soil.”

There are several concerns with very high levels of nitrogen, phosphorus and potassium in soil. High nitrogen can result in too much leaf g...