Down the Garden Path
Richard Hentschel, Extension Educator
Cucumbers, Squash, Zucchini, Pumpkins and Melons are all considered vine crops out there in the garden. Cucumbers are known for attracting cucumber beetles and a disease called cucumber wilt. Squash attract the squash bug and squash vine borer and a disease called powdery mildew. Pumpkins have issues with the squash bug and powdery mildew as well. How you handle these insects and diseases can make the difference between getting a crop, even it is only a partial crop and not getting anything from all your hours spent in the garden.
Cucumbers need to be protected from the cucumber beetle that will in turn spreads the cucumber wilt from the time the seeds are emerging from the soil until they start to vine and produce flowers. Even if the beetle infects the cucumber plant then, you will still get an good amount of fruits before the plant is impacted. If the cucumber feeds early, the plant dies before or just as it begins to produce for you. Cover the cucumbers with cheesecloth or floating row covers that keep the cucumber beetle from feeding. The cover has to be removed once flowering begins because the pollinator insects need to get to the male and female flowers. Zucchini is a prime target for the squash vine borer. The adult insect will lay an egg or eggs near the base of the plant where the very tiny borer larvae hatches, eating its way inside the stem. If unprotected you will see brown frass at the base of the stem because of what is now a much larger larvae eating much more and destroying the plant at the ground. An organic product like one of the "BT" treatments will manage the borer as it hatches before it gets into the stem. Once inside, little can be done. Be sure to cover the entire stem area from the ground up for several inches.
Squash bugs will hatch from a small cluster of eggs on the under-side of leaves and the nymphs will immediately begin to feed on plant juices. Later you will find them in large groups feeding on developing fruits, especially noticeable on pumpkins near the stem end. You will see squash bugs in all sizes from those that have just hatched to adults feeding together. The eggs are very easily spotted and routinely inspecting your plants will reveal those egg clusters. Crushing the egg cluster is simple and effective. Pumpkins also are prone to powdery mildew, which looks like powdered sugar, or finely grounded flower that has been sprinkled on the leaves. This normally shows up towards the end of the growing season, yet this year with the weather conditions we had is already around. As powdery mildew killed the leaves, there is less energy going into the pumpkins. This one will require a fungicide spray as soon as you see even a tiny bit as it will spread quickly.
Taking some preventative stems and scouting your garden will reward you many times over with an abundance of garden produce for your family and friends.
About the author: Richard Hentschel’s expertise extends across several subject areas with specialties in lawn care, fruit tree production, woody ornamentals, and home and community gardening. During his 45-year career in horticulture and agriculture, Hentschel became a well-known and respected expert for commercial and homeowner audiences, industry organizations, and media. He retired from University of Illinois Extension in April 2022 with nearly 30 years of service as a Horticulture Specialist and Educator in northern Illinois.