Typically, double cropping done after small grains is planting soybeans in wheat stubble, but not always, says Pennsylvania cover crop expert Steve Groff. Some growers plant a crop after barley, oats or other small grain crops, and cover crops are a viable choice for planting in late summer. The amount of precipitation is also a factor in deciding whether to plant cover crops after small grains. The type of cover crop planted can also play a role in helping increase yields the following growing year.