Observe Butterflies and Other Insects
Every season has it's gifts and late summer is a terrific time to observe and learn more about insects. I might grab a bug identification book one week and a butterfly encyclopedia the next. Don't just bury your nose in a book searching for names, however. Use a pair of binoculars to get a close-up view, then watch carefully. You'll be surprised how much you see and learn about different types of insects.
Add Vegetables for Fall
Time is running short for fall vegetable gardeners who like to eat what they grow. It's already too late to start seeds of broccoli, Brussel sprouts, cabbage, and cauliflower, so add these vegetables to the garden (ASAP) as transplants. In mid-August, sow beets, carrots, chard, and collards. Follow in September with kale, lettuce, mustard, radish, and turnips.
Germination of seeds can be especially difficult in the heat of late summer, especially when they are sown outside. Offset modest germination rates and surface dryness by sowing seeds more thickly and slightly deeper than usual. Then, cover the planting location with a piece of cardboard (kept in place with a brick) to help keep soil cool and moist. Water lightly each day, removing the cover as soon as plants begin to break the soil surface.
Make More Houseplants
Houseplants that have enjoyed a summer vacation outdoors should be at their best and ready to propagate. Some may have produced babies around the perimeter of their containers, or plantlets at the tip of their leaves or stems. Remove and pot up these babies, keeping them well-watered while they become established. Houseplants can be divided now, too. Simply take the plant out of the pot and gently pull sections apart, keeping tops and roots intact, and repot the sections with fresh potting soil.
Evaluate the Garden
As the summer season begins to wind down, take stock of the garden. Note the plants that didn't live up to expectations and those that exceeded them. Make a note of insect and disease problems, too. Most importantly, look for areas that need renewal. Fall is the best time to rebuild cool-season lawns, remake perennial beds, and plant woody ornamentals and spring-blooming bulbs.