Time your tomatoes
Publication Date: Friday Apr 18, 1997

Time your tomatoes

There's a lot to consider when planting this summer favorite

by Scott Loosely

QQ I am interested in planting some tomatoes this year. Is it too early to plant them now? When is the best time? AWith so little rain this spring, some days it seems like summer has already arrived. This beautiful weather makes us want to go out to the garden and start planting. Depending upon what you're planning to grow, you could be a little early or possibly a little late. If you were thinking of growing tomatoes from seed, you had better get hustling. It will take at least a week for your seeds to arrive if you have ordered them from a catalog. You could go to the local nursery and purchase seeds, but the selection may be limited. Hopefully your little packets are already in hand and you're ready to plant.

Tomato seeds can be started either indoors or directly in the ground. Sowing seeds in containers indoors will give you a head start on the season. You can start indoors as early as February. There are a variety of containers that can be used for starting seed. You can choose from clay or plastic pots, peat pots, peat cubes, Jiffy pellets, flats or even cut milk cartons. The container should be between two and four inches in size and have drainage holes in the bottom.

Fill the container with moist, sterile potting soil to within a half inch of the top. Plant one to three seeds one-quarter to a half-inch deep in the center of the pot. Water in the seed and place the container in the warmest spot you can find. Tomato seeds will germinate most rapidly with soil temperatures between 75 and 85 degrees. Keep the soil moist, but not wet, until the seed has germinated and the seedlings are ready to transplant. Placing the containers in a plastic bag until germination will help prevent them from drying out.

Tomato seed should germinate in five to seven days at the proper soil temperature. After germination, thin the seedlings to one per pot. Keep the new seedlings in full sun for as many hours as possible, or they will tend to get spindly. The optimum temperatures for seedling growth are 70 to 75 degrees during the day and 60 to 65 degrees at night. It will take eight to 10 weeks before the tomatoes are big enough to transplant--usually when seedlings have 4 to 6 true leaves.

Before you move your seedlings into the garden, a period of hardening-off should occur. This process lets your tender plants get accustomed to the outdoors. Set your seedlings outside in a sunny location during the day and protect them from the danger of frost by placing them under cover at night. After about a week, they will be more adapted to the outside temperatures.

If you are just getting started now, you can sow seed directly in the ground. Remember that the soil temperature needs to be between 75 and 85 degrees for optimum germination. If the soil temperature is cooler, you can expect germination to take longer. You may want to invest in a soil thermometer to check the temperatures in various locations in your yard. This way you can sow the first seed in the warmest area of your garden. Plant seeds one-quarter to a half-inch deep and water in. If you sow your seed too deep, it will take longer to germinate or the seeds might rot because the soil is too cool.

Before you sow seed directly in the garden, prepare your beds by digging in organic matter or compost to a depth of 10 or 12 inches. This is also a good time to add fertilizer for any nutrient deficiencies in your soil.

If you've waited too late to start from scratch and purchasing seed is not your thing, tomato seedlings are also available at your local nursery. The best time to plant these seedlings is when temperatures are in the 70s during the day and in the mid to high 50s at night. That usually corresponds to early May in our area. You can plant earlier, but if temperatures are low, the tomato plants just wait until it warms up. Another reason to wait for warmer temperatures is that most varieties will not set fruit if the night temperature is below 55 degrees. You just can't mess with Mother Nature.

When selecting your seedlings in the nursery, try to pick plants that are as wide as they are tall with at least 4 true leaves. Also look for plants that are resistant to verticillium and fusarium. These wilt diseases can ruin a summer tomato garden. Most of these varieties are also resistant to nematodes, too. These microscopic, parasitic worms feed on the roots, causing stunting and wilting.

If your soil is prepared, you're ready to plant. Tomatoes should be planted so that the first leaf is just above the soil. Unlike most other types of plants, tomatoes develop roots along the buried stem. If your seedlings are tall or leggy, lay the root ball and stem sideways when planting and bend the top upright. Your plants should be watered in well and you'll be harvesting tomatoes in a couple months.

Scott Loosley is the horticulturist at the Gamble Garden Center in Palo Alto. Send questions to Loosley care of Palo Alto Weekly, P.O. Box 1610, Palo Alto, CA 94302.

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