Northern California

Go shopping

Buy rhododendrons The renovated rhododendron garden at the San Francisco Botanical Garden is coming into bloom, and its designer, Georgia Madden of Feyerabend & Madden Landscape Design in Emeryville, recommends these early-flowering, easy-to-grow species: Rhododendron arboreum, a small treelike accent with red flowers and large leaves; R. ‘Noyo Dream’ for its overall form and creamy pink blossoms; and R. ‘Sabrina Adler’ with clusters of pale pink to white flowers for a vigorous but not too large foundation planting. These and many others are available from Sonoma Horticultural Nursery (3970 Azalea Ave., Sebastopol; 707/823-6832; no mail order).

Green your garden Shop for eco-friendly landscape ideas at this year’s San Francisco Flower & Garden Show.

Stock up on orchids Even those who don’t love orchids will be blown away by the Pacific Orchid Exposition, where you can check out more than 150,000 of these prized plants, many of which are available for purchase (Mar 6–8; entry fee $12 in advance, $14 at the door; Festival Pavilion, Fort Mason Center, San Francisco).

Plant now

Grow herbs  Sunset climate zones 7–9, 14–17: As soon as frosts are past, plant culinary herbs such as chives, cilantro, dill, mint, oregano, parsley, rosemary, and thyme in a sunny part of the garden.

Plant tomato seeds Zones 7–9, 14–17: Start tomato seeds indoors on a sunny south-facing windowsill early in the month, or about six weeks before the last expected frost. Organically grown seeds of 600 heirloom tomato varieties are available from TomatoFest Garden Seeds. Among site founder Gary Ibsen’s favorites for Northern California are pink ‘Julia Child’, purple-black ‘Black Prince’ and ‘Paul Robeson’, red ‘Aussie’, and yellow-orange ‘Kellogg’s Breakfast’.

Sow peas and potatoes Zones 7–9, 14–17: These crops like the cool growing conditions of early spring. In coastal areas, plant early in the month. In other areas, plant peas six to eight weeks before theast frost date, and potatoes four to six weeks before the last frost date.

Tend your plot

Apply fertilizer Zones 7–9, 14–17: Almost all plants, including annuals, perennials, trees, and lawns, will appreciate a boost of nitrogen now as spring growth starts, so feed with an all-purpose fertilizer. Wait until azaleas, camellias, and rhododendrons have finished blooming before feeding them; then use a formula labeled for acid-loving plants.

Double-dig planting beds To make maximum use of small vegetable planting areas, double-dig and amend the soil with compost so you can grow your plants closer together and water less. See how it’s done at Common Ground Organic Garden Supply and Education Center in Palo Alto (class Mar 14; $28; advance registration required; 650/493-6072).

Next: Plant romantic blossoms