Abundant spring rain encouraged lush new plant growth which now presents a target for insects.
I’m Lisa Hilgenberg from the Chicago Botanic Garden with tips for controlling damaging insects in your garden.
Identification of bugs will help determine how best to manage them naturally avoiding the use of harsh chemicals.
Aphids, sap suckers whose damage shows as reddish puckered foliage can be washed away with a strong spray of water from the garden hose.
Slugs damage Hosta plants this time of year and can be treated with nontoxic slug bait or by placing copper strips around prized plants.
Monitor vegetable gardens often, studying plants where damage may be obvious. Remove voracious eaters like tomato hornworms and cabbage worms by hand. Squish brown football shaped eggs of squash bugs found in clusters underneath leaves.
Egg cases of natural pest predators like Praying mantis can be purchased to set in the garden as biological control.
Japanese beetles emerge this month to skeletonize the leaves of 300 different plants like roses and grapevines. Handpicking emerald green beetles knocking them into a cup of soapy water is an effective control. Females lay eggs in the soil below lawns hatching into grubs that will be next year’s Japanese beetles. Keeping lawns drier or treating with Milky spore bacterium can help keep grub populations down.
Insecticidal soaps and horticultural oils can be applied with few ecological side effects. Sprays of garlic and mineral oil, pepper spray and dishwashing soap can be helpful.
Control should be aimed at suppressing pests at a tolerable level, not eliminating them completely.
Lisa Hilgenberg is the Regenstein Fruit & Vegetable Garden Horticulturist. She teaches classes for the Joseph Regenstein, Jr. School of the Chicago Botanic Garden and mentors interns from the Garden’s urban agriculture programs in the summer. Lisa draws on a rich family farming tradition, having spent many summers on her grandparents’ farms in Iowa and Minnesota. You can follow Lisa on Twitter @hilgenberg8.