Tomatoes (Lycopersicon lycopersicum)
Of all vegetables grown in residential backyards, tomatoes are the most popular. Perhaps it is because only vine ripened tomatoes have the richest flavor and tenderest skin, or maybe it is because they are the mainstay of so many wonderful recipes. Certainly it is because they are also so satisfying to grow. Tomato plants grow in small spaces, bear abundant fruit over 3 or 4 months, and require very little maintenance.

A warm season vegetable that originated in Mexico and Central America, the tomato comes in a bewildering array of sizes, shapes, colors, and flavors. Tomatoes are packed with nutrients as well, a typical fruit supplying more than 25% of daily needs for vitamins C, K, and A, along with over 1 gram of dietary fiber. A vegetable superstar today, the tomato was commonly thought to be poisonous to eat as recently as 1900.

Recognizing Tomatoes

Size of Plants:
Indeterminate plants, the most common, typically reach a height of 6 feet or more. Vine-like, they grow and bear fruit continuously until they are killed by frost. Stems need support as they grow heavy with fruit. See the file on Vertical Gardening for tips of supports for tomatoes.

Determinate tomato plants grow to a more limited size – not much more than 3 to 4 feet tall. They stop growing when they mature to the point where they set fruit at the tip of their main stem. Ideal for containers and small spaces, determinates grow more compactly, so they can be planted closer together.

Tomato foliage is medium green. Leaves are actually rows of 3 or 4 deeply lobed leaflets growing on each side and the tip of thin stems that branch alternately from the main stem. New dwarf types of tomatoes have crinkled, dark green leaves. Changes in leaf color signal nutritional, pest and disease problems.

Flowers & Fruit
About 2 or 3 weeks after transplanting outdoors, seedlings develop small yellow flowers which become tiny green tomatoes in a week or two. On indeterminate plants fruit forms in clusters at intervals along the main stems. On determinate plants it forms in clusters on tips of lateral stems and it usually ripens faster, making determinate types ideal for areas with short growing seasons. Depending on the tomato variety, fruits may be anywhere from 2 pounds to 1 ounce. They may be pink, yellow, orange, or even green. Their various shapes--plum, round, pear, oval and cherry--are suitable for numerous uses.

How Many Tomatoes to Plant?

Full-sized indeterminate plants typically produce a minimum of 15 to 20 tomatoes. Over a long season of good weather the yield may be as great as 50 or 60 per plant. Typically, 2 plants per adult and 1 per child supplies a family’s eating and cooking needs for the season. If you’re thinking of canning, then add more plants. For example, plant 2 to 6 extra plants for canning purposes for a family of four.

Buying Tomato Seedlings

It’s easiest to plant professionally raised tomato seedlings from the garden center. They are available in your area about the time it is safe to plant them outdoors. Choose seedlings with perky, rich green foliage and thick, sturdy stems. Avoid plants that already have flowers, as they are likely to be suffering stress. Make sure there are no woody patches on the main stem which may indicate that seedlings were overwatered or overfertilized in the greenhouse.

Seedlings come in market packs of 6 or 12 or in individual, somewhat larger pots. While slightly more expensive, potted tomato seedlings are likely to have more developed root systems--an advantage at planting time. Keep seedlings moist until transplanting time.

Although some venerable old-time favorite varieties are still available, the emphasis for seedlings is on hybrids, bred for disease resistance. Check plant labels for the initials V, F, N, and T after their variety name. They indicate that plants are resistant to common tomato diseases such as Verticillium wilt, Fusarium wilt, Nematodes and Tobacco mosaic.

Growing Tomatoes From Seed

If you grow seedlings directly from seed, you’ll have a much larger choice of tomato varieties and more control of the timing of your planting. Recent research shows that transplants grown from seed can be set out in the garden when they’re anywhere from 2 to 13 weeks old.

An overwhelming number of tomato varieties, both old-time favorites and modern hybrids, are available as seed. Look for the initials V, F, N, and T after their variety name on the seed packet--for example, ‘Roma VFN.’ They indicate inherent resistance to common tomato problems such as Verticillium wilt, Fusarium wilt, Nematodes and Tobacco mosaic. Choose tomato varieties recommended for your climate or zone. Finally, select for preferred color, size and intended use (slicing, salads, sauces, garnishes, canning).

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