Perennials: Remove and destroy all old foliage from your bearded irises after the first heavy frost — borers winter over on the old foliage. The ornamental grasses are at their best now so make notes for new plantings using this wonderful material. Leave some perennials for seed head interest and food for the birds, such as rudbeckia, Echinacea and caryopteris.
Flowers: Carry over some tender plants to stock next year’s garden. Dig plants from the garden and move them indoors shortly before frost. Nurture them through the winter and when growth resumes in early spring, take cuttings and discard the stock plant. The cuttings can be potted and grown to a healthy size ready to plant in the garden in late spring. Another method is to propagate plants from cuttings taken in the garden from geraniums or coleus or other short lived plants. It works well for those with limited space in a sunny window.
Vegetables and fruits: Continue harvesting and preserving if there is a bountiful crop. Be ready to cover tender crops during early fall cold spells. Basil can’t stand even a touch of frost, but lettuces will survive. Destroy all corn stalks and debris to prevent corn borers from wintering over.
Trees and shrubs: Many shrubs and trees will flower throughout the autumn. The Franklin tree (Franklinia altamaha) is stunning with brilliant crimson leaves and white blossoms appearing in late September. Some of the best shrubs for autumn leaf color include Burkwood viburnum, clethra alnifolia, spicebush and witch hazel.
Lawns: Weeds should be eliminated now and a good quality grass seed put down in bare spots.
Houseplants: Ease up on feeding houseplants until late January or February when the day length triggers the plants into new growth.
General: Again, summer had unusual weather with refreshing cool nights and plenty of showers. Lawns were green and lush, but other plants suffered.
— Susan Henry, master gardener with Cornell Cooperative Extension of Westchester