August 12, 2002

Summer is at its peak, but it's time to think about fall in the vegetable garden. Several kinds of vegetables can be planted now to extend the gardening season. Use any vacant spaces in the garden, such as where early spring crops have finished or where a summer crop succumbed to drought, pests or disease. Work in some compost or garden fertilizer to refresh the soil before planting the new crop.
Seeds of peas, beans, beets, carrots and radishes can be sown now. Select varieties of peas and beans with short harvest dates (noted on the seed packet) to ensure harvest before a hard frost. There is approximately two months until the date of our average first frost. Carrots and beets will keep very well in the soil even after a hard frost. Straw mulch applied over the crop later in the fall will keep them from freezing.
The cole crops (broccoli, cauliflower, cabbage and Brussels sprouts) should be planted now for a fall harvest. These should be planted as seedlings. They will grow well in cool weather and taste sweeter after a frost. These vegetables can be a favorite of the cabbage moth and the cabbage looper. Both kinds of larvae are green in color and sometimes go unnoticed until the damage appears. Holes will appear in the leaves and often only the midrib of the leaf is left. The seedlings can be sprayed weekly to control the caterpillars. Or you can grow the crops under a row cover to keep the insects off.
Lettuce, spinach and other leafy greens can be planted from now until early September. As the cooler fall temperatures arrive they will grow well without bolting to seed as they do during the hotter months. The fresh greens will be delicious with the ripe tomatoes. If cold weather threatens later on, use a row cover fabric to protect the lettuce from freezing night temperatures. The greens will probably last until late November or early December if they are kept under the cover. Some greens that are particularly good to grow in the fall include arugula, endives, romaine and the mesclen mixes.
Fall vegetable gardens can be very rewarding, especially if your summer garden was disappointing. Temperatures are cooler and rainfall is usually more reliable. And best of all very few weeds will be sprouting in the fall.
Late August through early September is the time to plant and divide the bearded irises. Iris benefit from being divided every 3-4 years. The rhizomes can be dug up and split into individual fans or divisions with a few fans. Trim the leaves back to make up for any root loss. Any rhizomes that are rotted or badly damaged by iris borers should be discarded. Plant the irises in a sunny location in average well-drained soil. Bearded irises are planted shallow, barely covering the rhizomes. Point the leaves in the direction you want them to grow, ideally out from the center. Water them after planting and mulch lightly for the first winter. They can be fertilized next spring.
This summer's heat and drought have once again been hard on the lawn. If a re-seeding project is going to be necessary this fall, now is a good time to go after the weeds. Weed killers can be applied now. After the weeds have turned completely brown rake them out and get the soil ready for new seed. A thin layer of compost or topsoil can be spread on the bare spots as well as a starter fertilizer for grass seed. A soil test can determine if you need to apply lime.
The trees and shrubs are also starting to show signs of drought stress. Some have wilting or browned leaves. And some are having pre-mature leaf drop. Many trees will drop leaves in order to preserve themselves through a dry spell. Take note of these symptoms on the trees and shrubs in your yard. Those showing signs of stress should be watered. A slow soaking once a week should help them through the prolonged dry spells. Check all evergreens carefully as they often don't show the signs until it is too late.

Beth Nardone, botanist, is a resident of Hillsborough and is the Nursery Manager at the Belle Mead Co-Op. Questions and comments can be sent to bethtanical@rcn.com