Time is running out if you hope to find bulbs at nurseries, and it may be too late to order them by mail from specialty growers such as easytogrowbulbs.com. Remember that not all bulbs do well here, but a few temperamental kinds can be tricked into blooming for at least one season.
Refrigerate tulips for six to eight weeks, and they think they've had a cold winter. Be sure to buy bulbs that are 2 inches or more across if you want blooming-size tulips. Toss out bulbs after flowering because they will not rebloom.
You'll get a smaller but longer show from Mediterranean climate bulbs, which come back year after year with no digging or care (as long as they stay fairly dry in summer).
Then flowers and vegetables
The sooner they get in the ground, the sooner that spring- and winter-blooming annuals will flower. Ditto with vegetables: The sooner you plant, the sooner you harvest. But wait much longer and seed becomes hard to sprout in the colder weather. Almost everything — and certainly plants from similar Mediterranean or temperate climates — does best when planted in autumn or early winter because a low sun and cool temperatures make life less stressful and rains can dramatically help with watering. Soils stay damp for weeks after a good soaking. Immediately stake new trees because strong winter winds can be a problem.
Now through early February may be the only time to plant our sometimes tough, sometimes tricky California natives, such as Arctostaphylos, or manzanita, and wildflowers. Make sure to plant natives a little high, with the crown about an inch above the ground, so the plant does not settle and end up too deep (instant death). Plant wildflowers in a weed-free area or they will be quickly overwhelmed (with the possible exception of the indomitable poppy), and protect the seed with bird netting.
Sow lawn seed
Bermuda lawns are growing and green in summer, dormant and sometimes brown in winter. Sowing seed of cool-season grasses on top, such as annual rye grass, fixes that. Scatter 1 pound of seed for every 100 square feet, lightly cover with a thin mulch (such as Kellogg Topper), and then water often enough to sprout the seed. Sowing seed too thickly can bring on a snow-like mold that kills the seedlings. Once the rye is about 1 1/2 inches tall, begin mowing and mow at that height. When warm weather returns, mowing it low will encourage the Bermuda and suppress the rye.
The neat garden
Unless plants have striking seed heads, it's time to tidy up by cutting back perennials, pulling dead leaves out of clumps and digging and dividing those that have grown too large. Dig and divide perennials; dividing controls their size and rejuvenates plants. Cut Japanese anemones completely to the ground for a fresh start.
Shrubs can be tidied by cutting dead branches and removing a few at random to let light inside. Make cuts artfully and the plant will look more natural and less hedge-like. Subshrubs such as lavender look better if they are lightly trimmed. Cut back too hard and you'll lose them.