What to do in your garden in September
Cool-season herbs and veggies. Prepare planting beds bydigging in a 6-inch layer of compost or well-aged manure. Sunset climate zones 1a-3b: Sow seeds of bok choy, carrots,chard, kale, lettuce, radishes, and spinach; plant garlic cloves.Zones 10-13: As soon as daytime temperatures stay below 100°,sow seeds of arugula, beets, bok choy, borage, carrots, chard,cilantro, dill, fava beans, kale, kohlrabi, leeks, lettuce,parsley, peas, and turnips. Plant onion sets and set outtransplants of broccoli, brussels sprouts, cabbage, cauliflower,chives, salad burnet, and winter savory.
Cool-season flowers. Zones 1a-3b: Sow seeds of cornflower,larkspur, and poppy for spring bloom. Set out transplants ofchrysanthemum, Iceland poppy, and nemesia. Zones 11-13: Set outtransplants of calendula, dianthus, feverfew, larkspur, pansy,petunia, primrose, snapdragon, stock, sweet alyssum, and viola. Sowsweet peas.
Rabbit-resistant plants. If bunnies are feasting on yourgarden, foil them with plants they’ll find distasteful: Agave,aloe, cuphea, emu bush (Eremophila), evergreen sumac (Rhus choriophylla), gopher plant (Euphorbia lathyris), heavenly bamboo, lantana, Mexicanevening primrose, pineapple guava (Feijoa sellowiana), plumbago, rosemary, salvia, Texasmountain laurel (Sophora secundiflora), verbena, and yucca.
Spring bulbs. Zones 1a-3b, 10-11: Plant spring-bloomingbulbs, including crocus, daffodil, grape hyacinth, hyacinth, andtulip. Zones 12-13: Buy hyacinths and hybrid tulips now; put thebulbs in paper bags and chill in the crisper section of yourrefrigerator until the soil cools down in early November, thenplant them in the garden. Botanical tulips (Tulipa species) don’t require prechilling; one good sourceis HighCountry Gardens (800/925-9387).
Control insects indoors. When spider mites, whiteflies, orother insect pests infest houseplants, try this recipe: To 1 gallonof water, add 2 tablespoons of mild dishwashing liquid (avoidcitrus-scented products, which can damage plants). Pour the soapysolution into spray bottles; spritz the foliage and soak thesoil.
Dig and divide perennials. Zones 1a-3b, 10: With a spade,loosen the soil around clumps of daylilies, hostas, peonies, andShasta daisies. Lift the clump out of the ground and use a sharpknife to divide it into pieces about the size of 1-gallon containerplants. Replant divisions immediately. Zones 11-13: Lift and dividecrowded iris rhizomes.
Keep up wildfire defense. Sweep debris from rooftops andgutters. Remove leaf litter and dry brush within 30 feet ofstructures. Prune dead wood from trees, cut away branches thattouch or hang over structures, and thin surrounding vegetation toreduce the fuel supply. Visit www.sunset.com/fire for morefire-protection advice.
Rejuvenate roses. Zones 1a-3b, 10: Let faded blossoms remainon plants to slow growth before winter. Zones 11-13: On hybrid tearoses, prune any dead or damaged canes, then cut remaining canesback by one-third. Fertilize and water thoroughly to encourage fallbloom.
TIP FROM THE TEST GARDEN
To produce coarse compost in one to two months, use a 50-50mixture of green and brown materials. Green matter includes grassclippings and vegetable scraps. For brown matter, use dead leaves,wood chips, or straw (not hay). For finer-textured compost, keepthe pile working for several more weeks.