What can you use to stop insects from eating your collard greens?

Beet army-worms, cabbage aphids, loopers and web-worms, cross-striped and imported cabbage-worms, cutworms, diamondback moths, flea beetle, harlequin bugs, onion and western flower thrips, salt-marsh caterpillars, southern green stink bugs and vegetable weevils are insects that eat garden collard greens. The above-mentioned list includes pests whose common names suggest non-insect invertebrates. Army-worms, cabbage-worms, loopers and web-worms actually represent moths in their larval (caterpillar) stages.