Evergreen vines. It's not too late to plant vines that bloom from late winter into spring. Favorites include white-flowered evergreen clematis ( C. armandii; Sunset climate zones 7-9, 14-17), fragrant pinkish white Jasminum polyanthum (zones 7-9, 14-17), pink or white Pandorea jasminoides (zones 16 and 17), and violet trumpet vine ( Clytostoma callistegioides; zones 8, 9, 14-17). All are very vigorous, growing 10 to 20 feet long or more.
Flowering cherries. Zones 7, 14-17: To prolong the bloom show, plant varieties that flower at different times. Try early-flowering, single, pink 'Akebono' or single, white 'Snow Goose'; midseason, bright pink 'Beni Hoshi' or double, rose-pink 'Kwanzan'; or late, semidouble, light pink 'Shogetsu' or double, pink to white 'Shirofugen'.
Tomatoes. Zones 8, 9, 14-17: Start seeds at the end of February for seedlings to plant out in April after the weather and soil warm up. Some of the tastiest varieties for Northern California gardens are 'Brandywine', 'Early Girl', 'Gardener's Delight', 'Green Grape', 'Stupice', 'Sun Gold', and 'SunSugar' (available from Tomato Growers Supply Company, 888/478-7333). 'Ace' and 'Celebrity' are flavor favorites in hot, inland areas.
Cool-season annuals. Sunset climate zones 7-9, 14-17: For instant color, plant annuals like calendula, cineraria, English daisy, forget-me-not, pansy, Iceland poppy, English and fairy primroses, Primula obconica, snapdragon, stock, sweet William, and viola.
Perennials. Zones 7-9, 14-17: Plant spring-blooming perennials like alstroemeria, bergenia, bleeding heart, brunnera, campanula, candytuft, catmint, columbine, coral bells, delphinium, dianthus, diascia, foxglove, Linaria purpurea, marguerite, and violet. Just before spring growth, you can divide summer- and fall-blooming plants such as agapanthus, asters, coreopsis, daylily, mums, and rudbeckia.
Summer bulbs. Zones 7-9, 14-17: Plan ahead for summer flowers and foliage. Plant tuberous begonia, caladium, calla, canna, crocosmia, dahlia, Asian and Oriental lily, Tigridia pavonia, tuberose, and gladiolus (try Gladiolus callianthus for fragrance, baby glads for short, loose spikes).
Care for fountains. If freezing temperatures are predicted, drain garden fountains, advises Jackie DeCesari, head of nursery and fountains at Sacramento's Silverado Building Materials. (Otherwise, sitting water can freeze, resulting in ice that can crack basins and pumps.) Then cover fountains with burlap or plastic.
Cut back woody shrubs and hedges. To stimulate lush new growth on artemisia, butterfly bush, and Salvia leucantha, cut back woody stems to within a few inches of the ground. Prune fuchsias back by a third and remove dead or crossing branches. If left unpruned, plants become leggy and scraggly-looking. Zones 7-9, 14-17: Toward the end of the month, prune boxwood, escallonia, laurel, photinia, and pittosporum. Doing so just before spring growth emerges helps shape shrubs into the forms you want. Use hand shears for the cleanest cuts; electric trimmers chew foliage.
Fertilize. Zones 7-9, 14-17: Late in the month, give perennials, shrubs, and trees their first dose of fertilizer for the season. (Wait to feed azaleas, camellias, and rhododendrons until after they bloom. Cool soil makes the leaves of these plants turn yellow this time of year. To green up their leaves again, feed the plants with chelated iron, per package instructions.) Feed roses in mid- to late February with a high-nitrogen fertilizer to give foliage a boost. Three weeks later, follow with a high-phosphorous fertilizer to encourage blooms. Merrill Jensen, director of horticulture for the Elizabeth F. Gamble Garden in Palo Alto, prefers an organic fertilizer like Down to Earth (800/234-5932).
Harvest citrus. Zones 8, 9, 14-17: Most citrus should be at their peak flavor now (the big exception is 'Valencia' and related oranges, which generally ripen from April into summer). Before harvesting the fruit, taste one to see if it's sweet (keep in mind that ripening time can vary from year to year, depending on the weather). Harvest as needed, but get fruit off the tree before it dries out or loses flavor, usually within two to three months (lemons are harvested year-round).
Mulch. In early spring (before weeds sprout), spread a thick layer of mulch over exposed areas to help keep weed seeds from germinating. A depth of 3 to 4 inches is usually sufficient for a medium-density mulch like mini bark. Keep the mulch a few inches away from tree trunks and the crowns and stems of plants to help prevent rot.
PEST AND DISEASE CONTROL
Discard fallen blossoms. Zones 7-9, 14-17: Azaleas and camellias are both prone to diseases called petal blight (caused by two different organisms), which result in flower rot. Azalea flowers cling to the leaves or stems; camellias drop from the plant. The best way to control the diseases is to remove (or pick up off the ground) and discard infected blossoms and avoid overhead watering. Apply 4 inches of organic mulch beneath camellias to reduce spore survival.
Dormant spray. Zones 7-9, 14-17: If peach leaf curl (a fungus that distorts leaves and weakens trees) has plagued your trees in recent years and you haven't sprayed them yet, do so once buds have started to swell but before they have opened. Use lime sulfur, and apply it with a spreader sticker when rain isn't predicted for at least 36 hours.
Slugs and snails. Zones 7-9, 14-17: As nighttime temperatures rise, snails and slugs become more active and can quickly destroy favorite plants, especially tender young seedlings. In the evening or early morning, handpick and discard them, or use an iron phosphate bait like Sluggo that's safe around children, animals, and edible crops.