Cover Crops – Plant Early and Often!

by Anne Verhallen

In the rush of the harvest don’t forget to plant those cover crops. It is easy to get busy and postpone cover crop planting but in the long run that is going to cost you. You can lose important growing time for cover crops – those warm days in the fall when we can get the maximum growth out of the plants.

This is a common problem in any area where winter can come suddenly but achieving maximum growth from cover crops is important. Work with cover crops in Ontario after wheat harvest has shown that 3 weeks difference in planting in the summer can almost double the biomass production. Earlier is the better when we are talking cover crops (usually)!

Sjoerd Duiker a Soil Management Specialist from Pennsylvania has found the same results, especially as the fall goes on. “Cover crop biomass accumulation and root growth depend on when the cover crop is established. This determines how much cover the cover crop provides and this is important for erosion control, especially when establishing a cover crop in a tilled seedbed, or with no-till in low residue situations (e.g. after corn silage, after soybeans, or when corn fodder is removed). Early establishment is also important so that the cover crop can absorb soil nitrate before it leaches to groundwater. In a study in the Mid-Atlantic region, cover crop nitrogen accumulation was about 120 lbs N/A in December when rye was established early, but was negligible in December if the cover crop was established late. The nitrogen that is absorbed by the cover crop is protected against leaching and is released next year when the cover crop biomass decomposes.”

One way to ensure that cover crops get planted in a timely fashion – keep a spreader or the drill ready to go with cover crop seed.

Note with picture – Barley planted early after vegetable harvest starting to head out in the fall. Mow if you are concerned about too much strawy residue. That will keep the plants vegetative and the residue easier to break down.