Southern California Coastal & Inland Valleys
Strawberries with whitish or yellowish leaves need to be fertilized one last time this year with a high-nitrogen fertilizer. After that, fertilize them only with a low-nitrogen, high-phosphorus, and high-potassium fertilizer such as 5-10-10 to help them harden off for the winter.
Transplant Bearded Iris
Trim bearded iris foliage fans to 8 inches from the rhizome. If they didn't bloom well last spring, divide the rhizomes. Dig up the whole clump, discard the old, leafless center sections, trim the roots of the newer sections to 2 inches in length, and plant them just below the soil surface, where they'll get as much sun as possible. Don't fertilize them, but water them in well after planting and every other week until the rains take over.
Building the Compost Pile
Fall is a good time to replenish your compost pile so that it will \"cook\" all winter. Spent annual flowers and vegetables, grass and other garden clippings, and non-greasy vegetable and fruit trimmings from the kitchen can all be added. Destroy or dispose of plants that are obviously infected with disease. Layer greenery with a bit of soil and dry matter such as hay. Keep the pile moist but not waterlogged, and turn it or loosen it every other week or so to let in air.
Planting for Fall Color
If you\'re impressed with the brilliant fall color of your neighbor\'s trees and shrubs, now is the time to shop for and plant many of those plants. Trees to choose from include ginkgo, liquidambar, Japanese maple, pin oak, red oak, Chinese pistache, Chinese tallow, tulip tree (Liriodendron), and zelkova. Shrubs include abutilon, cotoneaster, crape myrtle, escallonia, euonymus, hibiscus, holly, honeysuckle, oleander, pomegranate, and pyracantha.
Selecting Edible Cover Crops
If you're not planting a winter garden (and you should!), cover crops are an excellent alternative, even for home gardeners with small plots. While alfalfa, winter rye, and winter wheat are traditional choices that will hold the soil through winter and provide organic matter when tilled in next spring, edible cover crops are a way to get the best of both worlds. Kale and rocket (arugula) are leafy greens that withstand freezing, germinate in cool soil, and can be eaten all winter. Fava beans are also good since you can harvest the fresh seed in spring for salads, then turn under the greens, providing nitrogen fertilizer to your spring crops.