Also, burial of fruit containing sclerotia of the mummy berry fungus is difficult when the berries are lodged in the cover crop. In general, cover crops often involve more cost, maintenance, and management. Evidence suggests dwarf or intermediate perennial ryegrass competes with several horticultural crops, especially during the spring when the grass grows rapidly. Therefore, ryegrass should be managed by mechanical or chemical mowing. Chemical mowing is achieved using sublethal rates of a post-emergence grass herbicide.
Competition occurs with some crops even when the ryegrass is mowed.
This competition, however, is not evident in irrigated, fertilized blueberries. Four-year studies in British Columbia showed perennial ryegrass planted between raspberry rows depressed yields in unfertilized plots. Similar studies have not been conducted in blueberries. Companion grass, a blend of dwarf perennial ryegrass and creeping red fescue, is typically planted as a cover crop between blueberry rows. Organic Mulch A mulch can be used in blueberry plantings to reduce weed growth.