Image by Dwight Sipler
By Jackie Carroll
Kale plant protection for next year’s crop begins after the fall harvest. Many of the insects that damage kale and spread diseases overwinter in plant debris left in the garden at the end of the season. Fall cleanup, including disposal of plant debris and turning the soil to expose insects that spend the winter there, goes a long way toward preventing problems in the spring.
Kale Plant Protection
Another fall project to foil the diseases of kale is working compost into the soil. Most people know that compost is a great natural fertilizer, but did you know that it also helps the soil drain freely? Soil that can’t drain freely stays wet too long, and many fungi thrive in wet soil. Working in compost in fall allows it plenty of time to combine with the soil so that it is ready to manage water more efficiently in spring.
Kale pests also overwinter in garden debris and soil. Expose the insects to the harsh conditions at the surface soil by turning the soil several times over fall and winter.
Eliminating Kale Pests
Identifying and eliminating some of the most common kale pests can go a long way in your kale plant protection program. Common garden pests affecting kale include:
- Aphids – Allow natural predator insects to do as much of the work of controlling these insects as possible. If you must use an insecticide, use a soap-based product or neem oil. You may have to spray several times.
- Flea beetles – Good fall cleanup and weed removal are your best bet in controlling these insects, which chew tiny holes in the leaves. If these kale pests find their way to your plants anyway, choose an insecticide that is labeled for use against flea beetles and make sure the label states that it safe to use on kale.
- Caterpillars – You’ll probably notice moths darting around the plant before you see the caterpillars. In most cases, you can hand pick them. In severe cases, or if you can’t bear to touch them, you can use Bacillus thuringiensis, or Bt.
- Whiteflies – These tiny, whiteflying insects rise in a cloud above the plant. Use insecticidal soap or neem oil and spray every few days until they are gone.
Kale Disease Prevention
Starting a kale disease prevention program will help eliminate most diseases of kale in the garden. Begin protecting kale plants by implementing these control measures:
- Water the soil rather than the plant. Wet plants are more susceptible to diseases than dry ones.
Also, avoid splashing soil onto the plants when you water.
- Clean your tools thoroughly before moving from one part of the garden to another. Don’t forget your shoes! Bits of soil that travel from one part of the garden to another on the soles of your shoes may carry disease organisms.
- If you think your kale is infected with a disease, cut back on high-nitrogen fertilizers until you have it under control.
- Fungicides containing copper may help prevent disease infection or slow its progress, but they don’t cure diseases. By using fungicides early, you may be able to hold off the disease until after you harvest your crop.
Now that you know more about protecting your plants from diseases and garden pests affecting kale, you can enjoy a new crop each year without any worries.