Plant Cool-Season Veggies
Sow seeds for peas, root crops (beets, carrots, kohlrabi, onions, turnips), and green leafy veggies (arugula, Asian greens, chard, lettuce, mustard, and spinach). Sow seeds or transplants of cabbage family crops, including cabbage, cauliflower, broccoli, kale, Chinese cabbage, Brussel sprouts and bok choy.
Plant Cool-Season Flowers
Sow seeds for alyssum, bachelor's buttons, calendula, coreopsis, hollyhocks, Johnny-jump-ups, larkspur, nasturiums, pansies, and poppies. Set out transplants for baby's breath, petunias, stocks, dianthus, snapdragons, yarrow, and geraniums.
Plant Cool-Season Herbs
Sow seeds or transplants for borage, chamomile, chervil, chives, cilantro, dill, fennel, horehound, lemon balm, parsley, salad burnet, and French sorrel. Transplant the above, as well as lavender, lemongrass, lemon verbena, oregano, mint, sage, santolina, and thyme.
Plant bulbs from late September through November in the low desert. At higher elevations, plant before cold temperatures set in by mid to late October. Before planting, incorporate plenty of organic matter into the soil to improve drainage and fertility. Mix a phosphorus source, such as bone meal or bulb fertilizer, into the bottom of the planting hole. If gophers are a problem, encase bulbs in wire mesh cages.
Transplant Trees and Shrubs
Fall is the preferred planting time because then plants have about eight months of moderate temperatures for root systems to develop before summer's intense heat. Soil and backfill do not need to be amended for landscape plants. Loosen soil in an area that is five times as wide as the container. In the middle of this area, dig a hole as deep as the rootball or container and three times as wide. This allows the roots to spread easily through the soil. No fertilizer is needed for most landscape plants until they have been growing for a year. Many native plants don't require fertilizer at all, as they are well-adapted to soil conditions.