Seeds to Plant in Southern California in January

South Coast

• From the coastal county of San Luis Obispo to the Mexican border, January is the month to start cool-weather crops along the coastline. Sow both beets (Beta vulgaris) and carrots (Daucus carota) every two to three weeks from January through September for a continuous harvest. Endive (Cichorium endivia) is another excellent choice for succession planting from January through August. Preferring some of the coolest weather, kohlrabi (Brassica oleracea) and turnips (Brassica rapa) can only be planted in January and August. The time for planting a succession of several other crops also begins in January. Sow broccoli (Brassica oleracea) until February, peas (Pisum sativum) and rutabagas (Brassica napus) until March, leeks (Allium ampeloprasum) until April and parsley (Petroselinum crispum) until May. Plant peppery radish (Raphanus sativus) year-round.

Interior Valley

• In the fertile interior valley of southern California, nine different types of vegetable seeds can be started in January. Endive, parsley, leeks, onions (Allium cepa), radishes and all types of sweet and hot peppers (Capisicum annum) are ready to sow, and it is the last month to plant spinach (Spinacia oleracea) or peas until fall. Stagger a planting of broccoli over the months of January and February to extend the harvest. Spice up your salad bowl with a succession of lettuce (Lactuca sativa) cultivars planted every two weeks from January until March.

Desert Valleys

• While you can still plant cool-weather crops such as beets, chives (Allium schoenoprasum), potatoes (Solanum tuberosum), turnips and green onions in the desert valleys in January, your remaining choices are warm-weather plants. By taking advantage of the January through March planting window for bush and pole beans (Phaseolus vulgaris), it is possible plant a different type of bean -- such as yellow wax, Romano and yard-long -- every two weeks. To save space, consider smaller watermelon (Citrullus lanatus) cultivars such as “Early Moonbeam” and “Golden Midget”; you can tuck seeds in large pots or grow them on vines. Cantaloupe (Cucumis melo) is another good choice for container gardening -- sow seeds until April for a longer harvest.

Planting Tips

• If your soil has not been tested, this is a good time to use a home testing kit to profile its health and to add any recommended amendments. The foundation of your garden, vigorous soil leads to a better harvest. To prepare for planting, loosen the soil with a tiller or shovel, working in at least 1 inch of compost. Remove any weeds, and rake the bed to create an even planting surface. Moisten the soil before and planting, maintaining an even wetness until the seedlings emerge. Thin seedlings when they are around 2 inches tall.