What to do in your garden in September
Buy spring bulbs. Shop for anemone, daffodil, Dutch iris,freesia and other South African bulbs, and ranunculus while there’san ample supply. In the high desert ( Sunset climate zone 11), plant immediately; elsewhere, plantany time through October.
Order bare-root plants. Winter is the best time to plantroses and stone fruit trees, but if you already know what you want,place an advance order during Armstrong Garden Centers’ preseasonsale, which runs through October 31. About 700 kinds of roses,including 54 David Austin varieties, and 200 kinds of fruit treeswill be offered this year.
Fall in a pot. With the abundance of suitable-for-containerfoliage plants now available in copper and burgundy shades, everyhome gardener can enjoy autumn color, says Brita Lemmon of Brita’sOld Town Gardens (562/430-5019) in Seal Beach. Her favorites include ‘Ceylon’acalypha, ‘Toffee Twist’ carex, ‘Velvet Night’ heuchera, and’Cheryl’s Shadow’ geranium. If you want flowers too, add copperymums or ‘Terra Cotta’ million bells.
Herbs. Plant seedlings of mint, parsley, rosemary, sorrel,tarragon, thyme, and other perennial herbs. Sow seeds of arugula,chervil, cilantro, and dill.
Sweet peas. September and October are the best months toplant all varieties of sweet peas.
Winter vegetables. Starting midmonth, coastal (zones 22-24)and inland (zones 18-21) gardeners can plant winter crops. Sowseeds or plant seedlings of beets, bok choy, broccoli, brusselssprouts, cabbage, carrots, cauliflower, celery, chard, collards,kale, lettuce, green and short-day onions, parsnips, peas,potatoes, radishes, rutabaga, spinach, and turnips. In the highdesert (zone 11), plant lettuce, radishes, and spinach.
Feed most permanent plants. Fertilize established trees,shrubs, groundcovers, and warm-season grasses like St. Augustine.Feed roses one last time this year for a strong fall bloom. Don’tfeed California natives or drought-tolerant Mediterraneanplants.
Nurture camellias. To foster good bud development, keepplants moist but not excessively wet. Feed monthly through Januarywith a bud-promoting fertilizer, such as a 0-10-10 formula.
Pinch pelargoniums. To encourage winter blooms, prune backpelargoniums to new basal growth. Pinch back leggy impatiens aswell.
Shade seedlings. Protect transplants from sun with temporaryshade. Lay a window screen, supported by four stakes, over theseedlings. Or stretch a piece of shadecloth between two stakes,staple it, and place the structure on the south side of theplants.
Treat hydrangeas. To help blue-flowered hydrangeas retaintheir color, treat soil around plants now with aluminum sulfate.Use 1 tablespoon per foot of plant height or 1/4 teaspoon perpotted plant. Mix with water and apply to soil. Repeat treatmentlater in fall and again in early spring.