September in the Garden

When the foliage begins to yellow and die down on the late potatoes, stop watering so that the tubers are able to cure and "set" their skins in dryish soil before harvest. The tubers can be left in the round up to two weeks after the foliage has withered as long as they are well covered with soil.

Bring house plants indoors before the heat is turned on in the house. Clean the pots and wash the plants well. Then spray with insecticidal soap. Set the pots in some sort of half-way shelter such as a greenhouse or porch for 10 days to two weeks, and repeat the wash and spray routine before bringing the plants indoors.

Begin the autumn flowerbulb planting season with colchicums and fall crocus, the small, early spring bulbs such as snowdrops, crocus and dwarf iris, and daffodils. Pot flowerbulbs for winter bloom.

Late in the month transplant lettuce into frames for winter use.

Keep leeks and celery thoroughly watered, and pull soil up around the plants. Hold the celery stalks together, or tie them loosely, as you hill soil around them.

Watering can be tricky during September, when heavy dews make the ground appear damp. But September is almost always a dry month, requiring continued regular watering.

Sow fall rye on areas that are cleared of summer plantings.

As summer flowers begin to look disreputable in containers, replace them with fall and winter-flowering heathers, flowering cabbage and kale, crocus, and early dwarf daffodils such as Tete a Tete and February Gold.

Consider leaving some plants such as lettuce to set seed in the garden. They will provide food for the birds and an entertaining show of wildlife antics for the gardener.