For grubs, cabbage worms and most oher crawlie or flying critters, Try
buying a "floating row cover" and covering your cabbage (or any other
plant that does not require bee polination). The row covers are made of
some kind of very light, white material that lets rain and sunshine
thru...but NOT crawlie or flying pests.
If you treat them gently, you can use them season after season.

You put the row covers over the bed immediately after planting, leaving
enough 'slack" so the plant can get tall without pressing against the
material of the row cover. Make or buy "pins" (bent coat hanger wire) to
hold the row covers down.
Works great for chard, spinach, (any kind of greens), cabbage,
B.sprouts.

Obviously, not good for tomatoes or squash or any plant that flowers and
has to be bee pollinated.

Lass