Plant these vegetable-garden-friendly flowers once, and learn to recognize their seedlings. They'll return to help you fight the pests in your garden year after bountiful year.
1. sweet alyssum
10. Verbena bonariensis
Sweet alyssum (Lobularia maritima) wins the prize for being the hardest working flower in the vegetable bed, bar none, but you can't go wrong with any of the flowers on this top 10 list.
Queen Ann's lace type flowers (cilantro and dill) join sweet alyssum in attracting large numbers of hover flies and parasitic wasps. The hover flies lay their eggs on broccoli, lettuce and other aphid-prone plants. When the larvae hatch, they hang out on the undersides of leaves, patrolling for pests. A single young hover fly maggot can eat 400 aphids before it retires into its nectar-sipping adulthood. Parasitic wasps lay their eggs right into aphids, caterpillars, leafhoppers, and other undesirables, consuming them from the inside out.
Buckwheat is a champion summer cover crop that does double-duty by bringing in predatory flies, lady beetles, lacewings, and other garden friends. Let it go to seed and it will self-sow with abandon.
Members of the sunflower family: cosmos, calendula, feverfew, and sunflowers, are happy additions to the garden for lots of reasons. They keep necessary pollinators close at hand as well as attract predatory wasps and flies. Birds often perch on sunflower stalks, surveying the garden for a bug feast.
Amaranth provides habitat for beneficial ground beetles, which feed on beetle eggs, small larvae, and sometimes slugs(!), and supplies plentiful seeds for birds. Last but not least, if you'd rather watch butterflies flit about in your garden than flies and wasps, Verbena bonariensis is the plant for you.