Worms that feed on Cabbage, Cruciferous vegetables, Brassicas, Green leafy vegetables, Cauliflower, Chinese Cabbage, Garden cress, Water Cress, Broccoli, Brussels sprouts, kale, kohlrabi, mustard greens, radish, turnip etcetra.
Imported Cabbage Worm
Celery worm also known as carrot caterpillar and parsley worm does not feed on Cabbage or Brassica but is a prolific pest of similar crops -which include carrots, celery, parsley, dill, and parsnip. They chew The foliage and stems and destroy green tops.
Parasitic Wasps, Ground beetles, syrphid fly larvae, spiders. Lady Bugs, Praying Mantid.
Spinosad is another biopesticide , correctly termed a microbial pesticide, harmless to humans. Spinosad will interfere with pollinators as well as pests - evening / night time use is advisable.
Bt - bacillus thuringiensis. - Diamond Back Moth has developed some resistance to it - has proven effective against garden worms , it is a bacterium / organic pesticide that is readily available to home gardeners. It's harmless to people and pets. It's not a miracle cure but as stated , it is highly effective. Apply it at either bloom or petal fall, or both. Bt It is a stomach poison and must be ingested . It is more effective when applied during warm, dry weather while the larvae are actively feeding. Bt breaks down quickly in nature so multiple treatments per season are necessary.
Neem and various derivatives of their active ingredient Azadirachtin are an effective Biopesticide that works by interrupting the insect's growth cycle resulting in its early death.
Diazinon can be applied at petal fall, but is not as eco-friendly as the bio-pesticides listed above as it is toxic to beneficial insects and pollinators. Other Broad-spectrum insecticides, such as pyrethrin or malathion only as a last resort, generally used commercially and not really advisable for smaller plantings or home gardeners.
Most Sprays/Pesticides must be applied in the pre-bloom stage to prevent injury. Do not apply insecticides, even bio-pesticides during bloom time to protect vital pollinating insects.