If you love to grow your own vegetables from seed, particularly tomatoes, peppers and eggplants, December is the time to get them started in the Southwest. Growing from seed allows you a much wider range of varieties than what you normally find at the nursery. It also allows you to experiment with heirlooms, open-pollinated varieties, or even those you kept yourself.
To plant seeds, fill a clean container with sterile potting mix, such as Miracle-Gro® Potting Mix or a mix of equal parts vermiculite and Miracle-Gro® Perlite. Water well and firm the medium. Use a container that drains, but is no more than 2 inches deep. Drop seeds on the top of the medium, pressing them in with a small tool like the eraser end of a pencil or a chopstick and backfill over the seeds. Vegetable seeds need to be planted only 1/4 inch or less below the surface. Place in a warm, sunny, location and cover the pot with a clear, plastic storage bag (freezer bags are not recommended; they are not porous enough) or a milk or juice jug with the bottom removed. Water only when the surface of the medium is dry or you see no water droplets on the surface of the covering.
Time to germinate depends on temperature but is within 4 to 6 weeks of planting. Once the seedlings have 2 sets of leaves, take off the covering. Put them in a warm, protected location that has strong but indirect light to prevent them from becoming leggy or weak. Fertilize weekly with a diluted solution of fish emulsion or water-soluble fertilizer, such as Miracle-Gro® Water Soluble All Purpose Plant Food, until they are transplanted. Out in the garden, continue planting a wide array of winter vegetables to maintain a crop throughout the winter.
Most greens are fast-growing enough to plant in succession at 2- to 3-week intervals. Good choices to plant now are lettuce of all types, but especially leaf lettuces, spinach, broccoli, raab, and Swiss chard. Oriental greens like Chinese cabbage, bok choy, and tatsoi are quick-maturing greens that are ideal for succession plantings. Radish in any variety and turnips, especially Tokyo Cross, are also fast-maturing and easy to continue to plant in December.
Slower-maturing crops like beet, broccoli, parsley, dill, fennel, carrots, as well as transplants of asparagus, artichoke, both Chinese and garlic chives, bunching onions, and mints can be planted in December.
This is the beginning of the coldest time of the year, even in the warm desert, so it is important to adjust watering schedules for vegetables. Water to a depth of 8-12 inches, reducing the frequency so that the soil column is half-dry between waterings.
