Continue to water deeply – less often.
Continue to dead head spent blooms on perennials and annuals to encourage more flowers. This includes tomato plants; remove extra foliage to encourage fruit production.
Colorful fall annuals such as mums, pansies and cabbage and kale are available in garden centers now.
Try to purchase plants with flowers still in bud to extend the bloom color time.
Plant cool-season leafy vegetables like lettuce, spinach and arugula. The warm soil temps will encourage quick germination and mature plants before frost sets in. Keep leaves off of the vegetables if we get an early leaf drop from trees.
Now is the time to plan for spring bulbs. Check out your local nursery or on-line catalogs and go for big bold colors! After the winter doldrums, you’ll be very excited to see these first bursts of color in spring. You can also plan out a sequence of colors by noting the bulb’s bloom times and planting in chronological order.
Crocus is one of the earliest bulbs to bloom and offer a delightful color contrast to late-season snowfall.
Take inventory of your “stiff and upright” perennials. These include ornamental grasses, coneflowers, and many other native plants. You’ll want to let them finish flowering and go to seed and keep for winter interest. These also provide a source of food for birds in winter.
Other plants will begin to fade, their leaves will turn yellow and rest on the ground. Clean these up as they fade for a tidy-looking garden.
Stay on top of weeding. September usually sprouts a variety of weeds. If you can’t keep up with pulling weeds, at a minimum cut off flowers and seed heads and dispose of in an off-site compost waste stream.