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    Save the Date: Perennial Plant Society’s 30th Plant Sale is April 4, 2020, 9 a.m. – 1 p.m. at the new Expo 3 Building at The Fairgrounds Nashville. Here’s where you can find the newest varieties of perennials, shrubs, vines and annuals from local growers, along with long-time, never-fail favorites, ready for spring planting. Learn more at the PPS website.

     

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Stinkbugs, harlequin bugs plague late-summer gardens

There are flat, brightly colored bugs all over my cabbage and broccoli plants right now. What are they? Are they harmful? How can I get rid of them?
Harlequin bug copy

What you see plaguing your plants are, no doubt, harlequin bugs, and yes, they are harmful to your plants in the brassica family – broccoli, greens, cabbage turnips and kale. This time of year, the bugs you see are probably the adults. They use piercing mouth parts to extract the juices from all parts of the plants, and heavy infestations can cause severe damage – you may see discolored spots on the plants. The leaves of young plants may wilt and die, and mature plants will become stunted.

Getting rid of them can be a challenge. Toxic Free NC, A website devoted to non-toxic solutions to pest problems, suggests removing them by hand if there are only a few (drop them into a bucket of soapy water), or if there are large numbers and you are willing to sacrifice the plants they have damaged, trap them in large garbage bags, seal the bags and let them bake in the sun for a few days.

It’s always good to encourage the natural predators of damaging insects to visit the garden. Praying mantises eat harlequin bugs and other stinkbugs, so if you see them around, don’t shoo them off. There are parasitic flies and wasps that are among stinkbugs’ natural predators, and birds, spiders and toads also enjoy them as a food source.

As a last resort, Toxic Free NC suggests insecticides that are approved for organic farms, such as rotenone, pyrethrin, Neem oil and insecticidal soap. Note that these products can be harmful, so be sure to follow label directions and use as little as possible. These insecticides can also kill the bugs you want to keep, so spray only in the morning or late evening when those insects may be less active. Insecticides are most effective on the pests in the younger larval or nymph stages. The adult bugs are resistant to sprays.

To prevent the bugs from finding your plants in the first place, Toxic Free NC suggests using lightweight floating row covers over your brassica crops, making sure the edges are weighted so the bugs can’t get to the plants. It also helps to control weeds in the garden, as stinkbugs are attracted by weedy areas in or near the garden, they advise.

The garden’s second season

QUESTION: When should we start planting a vegetable garden for fall?

seed packetsStart now! As summer vegetables begin to dwindle and fade, make space in garden beds for kitchen garden favorites that grow in cooler weather. Here are suggestions and tips from garden authors and extension agents:

Broccoli: If you can buy transplants, make sure they are short and compact and have good, green color. Be sure they’re not transporting pests or disease. Plant them in full sun about 18 inches apart, with about 36 inches between rows. Water as needed to keep the plants from wilting, and apply a complete fertilizer when they are about 10 inches tall.

Cabbages: Set out transplants in full sun and well-drained soil. Space the transplants 12 to 18 inches apart with 24 inches between rows. Fertilize the plants when they’re about half grown, and harvest when the heads reach full size. For the best flavor, use it fresh.

Collards: Sow seeds or set seedlings in full sun and well-drained soil, 12 to 18 inches apart, with 20 inches between rows. Provide regular water (about an inch of water a week) and harvest by cutting the outer leaves as they reach full size.

Leaf lettuce: Begin now to sow seeds in successive plantings every two or three weeks. Sow in rows 12 inches apart, and thin to 4 – 6 inches apart when seedlings appear. Seeds can also be sprinkled over the soil in large pots and planters. Harvest when the leaves are large enough to use.

Spinach: Sow seeds in full sun in rows that are 12 inches apart, and thin then seedlings to one plant every 6 inches after they begin to grow. Provide regular water, and harvest when the leaves are large enough to use.

Turnips (greens or roots) Sow seed in full sun and well-drained soil, ½ inch deep, eight to ten seeds per foot in rows 12 inches apart. When the seedlings are 4 inches tall, thin them to about three inches apart. You should have greens to harvest in about five weeks. If you grow turnips for the roots, harvest them when they are about 2 – 3 inches in diameter.