Northern & Central Midwest
Fertilize Vegetables and Annuals
This is a good time to give your vegetables and annual flowers a last shot of fertilizer before they begin to wind down. Another side dressing of compost or composted manure is a good low dose that will keep them blooming and healthy into the fall.
Harvest Vegetables When Young
In most cases, harvesting will keep the plant producing longer, so pick those zucchinis when they are 3 or 4 inches long. Pick your cukes early as well, and tender succulent immature pole beans will simply melt in your mouth. Tomatoes, peppers, and eggplants, however, need to be mature.
Let Plants Go To Seed
Let some plants go to seed to start the fall garden. Cilantro and dill will give you plants for the fall and following spring if you let just one or two plants set seed. Lettuces, endive, arugula, mustard greens, and Chinese cabbage will plant your fall garden for you if let them go to seed.
Leave Perennial Seedheads
Don't be too quick to cut off perennial plants as they finish blooming. Leaving seedheads on coneflowers, black-eyed Susans, and just about anything else in the daisy family will draw birds and scatter seeds for more plants next year. Some annuals, such as impatiens, petunias, snapdragons, and salvia, will reseed themselves for next spring.
Clean Up Fallen Fruits
Start cleaning up the orchard as fruits abort to keep the job manageable. Plums that fall or stay on the tree with black rot should be discarded as soon as possible to prevent reinfection. Clean up apples, pears, peaches, and grapes and send the culls to the compost bin.