Lobularia maritima. Sweet Alyssum makes an excellent cover crop for weed suppression and for attracting beneficial insects. A very large range of predatory wasp species are attracted to its tiny flowers, and will feed on caterpillars, aphids, and other pest insects while they are in the area. Sow Alyssum liberally between rows of lettuce, carrots, or Brassicas to smother potential weeds and generally improve the garden ecosystem. Once it is tilled under it will release useful carbon and organic matter.
The fast growth of this annual helps to smother weeds. At the same time, its tiny flower clusters attract beneficial predatory insects that will combat pest species throughout summer. The purpose of this cover crop is not to build soil as much as to generally benefit the garden. This is exactly the same seed that we sell for flower gardens, only in bulk sizes with cover crop instructions.
Exposure: Full sun to partial shade
Direct sow when a slight risk of frost still exists
Sow seeds on the surface of the soil. They should sprout in 5 to 14 days, depending on conditions.
Alyssum can be tilled under or cut and composted at the end of the season. Avoid following this cover crop with other Brassicas. Excess moisture in the soil causes Alyssum to grow very vigorously.