Our ornamental landscape beds are really going through the process of getting ready for winter in a big way now. The weather pattern with warm days and cooler to cold nights has triggered the plants physiology from one of active growth to that of preparing for dormancy. Once that begins, there are clear signs, like fall color development and diseases like powdery mildew that can be seen now on a great many plants.
Late fall vegetable gardens are really benefitting from our recent weather and all the soil moisture that has built up with our rains. Unless unexpected freezing weather takes those plants down, harvest will continue for several weeks yet. Kale has been doing very well this summer and remains quite robust in the garden. Swiss chard and all its colorful foliage is another vegetable that should last quite a while yet.
Plants that have finished for the season include snap beans and tomatoes. Tomatoes more so for all the foliage diseases that have attacked. Our vine crops like warmer weather for the most part and by late summer the foliage's are fading badly because of Powdery Mildew. That is why we notice the pumpkin fields all of a sudden; the leaves are collapsing, exposing the pumpkins for the first time all summer.
Needle evergreens are at risk, remaining stressed and in decline for the past two years. Late season watering is one way to help them recover. Master Gardener Help Desk calls continue to be about spruce needle diseases and arborvitaes browning to the tips or losing an entire branch from the ground up. Besides the late fall watering, a plan to fertilize them next spring should be put in place. Whenever you are going to fertilize, do so when the plant can take best advantage of your efforts. Pines have their share of needle blights and casts as well.
Lawns have been a bright spot, using the cooler weather and rains to rebuild and thicken the lawn. That renewed vigor also means the need to mow more often. The spots that have not come along very well include those where the sun shade pattern has changed, leaving the lawn too shady in spots, resulting in thinner areas. Check out what is causing the actual problem. In some cases, limbing up the tree to increase the amount of sunlight reaching the ground for even a couple more hours can make a big difference. If you have a shrub border around the yard, be sure it is free of our more common "weed tree" that can quickly grow up and prevent sunlight from entering the yard. It is that early morning or late afternoon sun that can make the difference between just struggling along and actually growing. Those spots along the driveway or sidewalk or where the pets consistently run where compaction happens will also prevent the lawn grasses from doing well.
Continue to enjoy the changes out in the yard while you work to get the beds, trees, and shrubs ready for the winter and what it brings.
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.