The cabbage white butterfly may be a sign of spring, but it isn't always welcome in the garden. This white, black-spotted butterfly is one of the most common garden pests, attacking cabbages and other mustard-family plants. They lay eggs on cabbages, which hatch into worms that do considerable damage to the plant. Use a few simple, inexpensive measures to help deter white butterflies from the garden.
Plant French marigold, Tagetes patula, or pot marigold, Calendula officinalis, among your cabbage plants. Space these flowers at least 18 inches from the cabbage to give both plants room to grow.
Plant dill or sage near your cabbage plants. Space dill 18 inches and sage 24 inches from the cabbage to allow room for plant growth. Allow the dill to flower because it attracts wasps that feed on the cabbage worms.
Cut strips of white plastic bags 2 to 3 inches long and 1 to 2 inches wide. Tie these in a bow to the top of thin bamboo, plastic or other sticks. Place these around your cabbages to create the appearance of cabbage butterflies, which may help repel real cabbage butterflies.
Cover the entire cabbage planting with a floating row cover made of insect-proof netting. Seal the entire edge of the row cover with dirt or heavy items like bricks or metal pipes to prevent butterflies from entering.