Landscape care strategies have certainly changed since it has gotten dry and hot, and now we have gotten scattered rain events giving water to some and not others.
We are seeing the end of the spring bulbs with foliage yellowing and drying down, which is accelerated by the hot dry conditions. The early spring bulbs "went away" some time back, now it is the daffodils. Other perennials, like columbine and bleeding heart, really do not like the hot weather and those too are fading away.
Lawns have taken on a different look with the hot weather. Major grass types that thrive in our area are known as cool season grasses, preferring spring temperatures and rainfall. Lawns have slowed in growth with the heat and do not have that rich, dark green color now. If the weather pattern does not change, natural summer dormancy may start earlier than expected. Continue to mow as needed, removing no more than one-third of the grass blade at any one mowing. If you started out the season with a sharp mower blade, it is already time to re-sharpen or touch up the blade, as we have lots of mowing yet this summer.
Fruit tree growers are changing over from the early spring sprays protecting foliage and fruit buds from spring diseases to what is commonly called "cover sprays" for the rest of the season up until a couple weeks before harvest is expected. Cover sprays continue to protect both foliage and quickly developing fruit from insect feeding and egg laying activities from codling moth (the original worm in the apple) and apple maggot caused by a summer fly. Both insects really ruin the fruit for consumption. Cover sprays also protect from minor fruit diseases like fly speck and sooty mold, both being superficial on the skin of the fruit, but very unattractive. Be sure to read the label of the product you are using to be sure you are making the treatments at the right intervals.
Plants have mature leaves by now, and insect feeding and diseases still can take their toll out in the landscape. Symptoms differ enough that gardeners can figure out what needs to be done next. Foliar feeding insects like beetles and caterpillars will leave a clean clear margin as they feed. Foliage diseases will leave a tattered edge often times with a margin of dead cells. Some insect feeding is normal and expected. It is when lots of leaves are being impacted that a treatment may be warranted. Think Japanese beetle. The other common kind of feeding insects are those that remove plant sap, like an aphid or scale insect. Feeding occurs from the underside of the leaves or on younger twigs and branches and not readily visible. There is a clue – sticky sap on the upper side of leaves and sappy spots on anything underneath the tree.
Last, but not least, be sure to keep watering newly planted plants and key established plants in the landscape.
Richard Hentschel is a Horticulture Extension Educator with University of Illinois Extension, serving DuPage, Kane and Kendall counties. Stay tuned to more garden and yard updates with "This Week in the Garden" on Facebook at facebook.com/extensiondkk/videos.
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.