Certain holidays defy the calendar. Just as Memorial Day is viewed as the unofficial start to the summer season, Labor Day is regarded by most as the unofficial beginning of fall. Many folks also think of one as the start of the gardening season and the latter as the end of the gardening year. Of course, all this thinking boggles the mind of strict devotees to calendars. Fortunately, I don't think at all -- as should be obvious to regular readers of this column. That's why I'll keep plodding along with this gardening year since there is so much to do:
n Evaluate plants in perennial borders. Look for plants that are being crowded or are crowding other plants, those looking ratty due to pest and disease, and those that just don't offer much in terms of flowers or foliage. Make a note to divide the overgrown ones next spring. The others may be best treated by simply ripping them out of the garden. There are so many great plants on the market, why fuss over those that are prone to pests and disease problems or that offer little ornamental value?
n Rejuvenate old or over-crowded peonies by digging up the root clump and dividing the rhizomes (underground stems) into sections, each containing at least three eyes or buds. Replant the divisions so that the rhizomes are no more than two inches below ground. How do you know a peony is old? If George Washington slept beneath it, it's probably too old. Otherwise, an indication of old age is a steady reduction in number of blossoms produced in the spring.
n Check mums for leaf tiers. Leaf tiers are caterpillars that exude silken threads to tie together the leaves upon which they are feeding. Leaf tiers can be found on a wide variety of plants throughout the growing season, and mums are a favorite host at this time of year. Normally, I don't worry much about this insect pest but with mums about to begin their floral display, I try to preserve the attractiveness of the plants by applying a natural pyrethrum based insecticide to control the leaf tiers.
n Plant autumn crocus (Colchicum autumnale) to add additional color to the fall garden. Interestingly, only the flowers appear in fall. The leaves appear in spring and then fade away as summer heats up.
n Use a slow-release or organic fertilizer to feed the lawn this week. As temperatures cool, grass begins to grow with renewed vigor, especially if given a boost from a fertilizer application. If you make just one application of fertilizer to the lawn, this is the time to do it. Grass is recovering from summer stress; new root growth is beginning; and grass must be restored to good health if it is to survive winter.
n Take cuttings from fuchsia, wax begonia, coleus, African daisy (Osteospermum), geraniums, lavender, rosemary and other garden plants for growing indoors this winter. After dipping cuttings in a rooting solution or powder, stick them in pots or flats of vermiculite, perlite or clean sand for rooting. Once rooted, pot up the plants and place them on a sunny windowsill or under fluorescent lights. In late winter, cuttings can be taken from these houseplants to make plants for the summer garden.
n Plant annual rye or oats in vacant areas of the vegetable garden or between rows of sweet corn, tomatoes and other widely spaced crops. Annual rye and oats will die over the winter, but the dead plants provide good soil cover through winter and contribute significant amounts of organic matter when tilled under prior to spring planting.
n Plant trees, especially needled evergreens, shrubs and perennials this month (September). Soils are still warm and roots of new plantings develop quickly at this time of year.