• slide
  • slide
  • slide
  • slide
  • slide
  • slide
  • slide
  • slide

Holes in Cabbage, Broccoli and Kale leaves

Have you noticed those beautiful white butterflies flitting across your garden?  Lovely to look at, but what they leave behind is a problem for gardeners.

The larvae of this butterfly as well as the diamondback moth and cabbage looper eat holes in the leaves of cabbage, broccoli, kale, collards and their relatives.

Nature helps control these pests.  Parasitic wasps, ground beetles, soldier bugs and lacewings are all natural predators of these insects.   You will need to tolerate a little damage and avoid using pesticides in your garden so these good guys will move in and help control the pests.

Regularly check along the stems and between leaves for the gelatinous eggs and green caterpillars.  Destroy whatever you find.

Or try the environmentally-friendly Bacillus thuringiensis (Bt) sold as Dipel or Thuricide.  The Bacillus thuringiensis, known as Bt, bacteria kills only true caterpillars and is safe for people, pets, wildlife and other types of insects.

A bit more information:  Prevent the damage by covering these plants with a floating row cover sold as ReeMay, Harvest Guard or Grass Fast.  These polypropylene fabrics allow air, light and water through, but prevent the butterflies and moths from laying their eggs on the plants.  Cover the planting with the fabric anchoring the edges tight to the soil with stones, board or other heavy items.  Leave enough slack for the plants to grow.  Simple and eco-friendly.

Upcoming Live Events
& Webinars

Jan. 28, 2026
FREE WEBINAR: 
Past, Present & Future of Mitchell Park and its Conservatory, the Domes  
Register here

Feb. 13 - 15, 2026
PBS Wisconsin
Garden & Green Living EXPO

Madison, WI
More information

Feb. 18, 2026
FREE WEBINAR: 
Plants that Go the Distance
Register here

Feb. 25, 2026
FREE WEBINAR:
Flowering Houseplants

Register here

Mar. 5, 2026
FREE WEBINAR:
Start New Plants from Seeds, Cuttings and More

Register here

Mar. 11, 2026
FREE WEBINAR:
Save Money & Boost Your Growing Success with Bare Root Plants

Register here

Mar. 18, 2026
FREE WEBINAR:
Patio, Deck and Balcony Gardens

Register here

March 26, 2026
FREE WEBINAR: 
Getting Started Growing Vegetable and Flower Gardens
Register here

WATCH ON-DEMAND WEBINARS

Learn More

Book an Appearance

Learn More

Enter for the chance to win a Milwaukee Domes Alliance membership & merchandise!

ENTER NOW