Starting Tomatoes From Seed

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When starting tomatoes from seed they'll look something like this in their early stages.

Starting tomatoes from seed is a necessity if you want to try multiple tomato varieties, since most just aren’t often available as already started plants. Don’t be frightened off, though … you’ll find that it’s easy as well as inexpensive to raise your own “starts.” Here’s how:

First, get out your calendar and mark the occurrence of the last frost in your area (you can get the information from your county agricultural agent) . . . then count back six to eight weeks. The date you come up with is when you should plan to start your tomatoes-to-be.

To germinate the seeds, you’ll need some soilless mix (sold under such names as Jiffy Mix, Pro-Mix, Metro Mix, or Terra-Lite Tomato Soil . . . and available through seed catalogs and garden centers), some seed flats to hold the mix, plastic bags for “instant greenhouses” to enclose the flats in, milled sphagnum moss (not peat moss), and a source of mild heat–75 to 80°F is ideal. Use an electric heating pad, tray, cable, or a well-insulated radiator or heat pipe.

Now fill the fiats with the soilless mix and dampen ’em well . . . sow the seeds on top (spaced an inch apart) and cover them with a half-inch layer of milled sphagnum . . . wet the moss thoroughly . . . put each flat in a plastic bag. . . close the sacks with twist-ties … and place the “incubators” on the heat source. The sphagnum moss will prevent damping-off disease, the plastic bags will retain the moisture so you won’t have to water until the little plants are up, and the heat will really speed up germination. In fact, you can expect the seedlings to become visible in about a week.

Once the young’uns are up, brace the plastic covering so the plants don’t touch the damp material (the bag can be discarded when the seedlings are about a week old), remove the flat from the heat source, and grow the sprouts–at about 60°F–an inch or two under a twin-tube 40 watt fluorescent light fixture. (The lamplight “day” should be between 14 and 16 hours long.) Raise the little plants under these conditions until they’re two to three inches tall and have at least one set of true leaves (not just the cotyledons that are the first to appear). At that point, you’ll be ready to perform the first transplanting.

Gather together some three inch flowerpots (plastic cups will also work fine), fill them with the soilless mix, and carefully lift the seedlings from their trays and place them In their new homes. In transferring them, set the immature plants deeper than they were growing in the flat . . . even if you have to nip off the lower leaves. Tomatoes have the ability to sprout roots all along their buried stems, so deep planting will help produce substantial root systems. Feed the seedlings each time you water by giving them a quarter-strength dose of soluble houseplant fertilizer, and continue growing the young vines under the lights until they are about 10 inches tall.

Now it’s time for the second transplanting … this time into half-gallon milk cartons (or similar-sized containers). Again set the plants deep: Remove all the lower leaves, and–with the roots touching the bottom of the carton–bury the denuded stem almost up to the top.

Of course, the entire purpose of double transplanting is to produce stocky plants with substantial root systems, not to rush fruiting. So, if the vines do develop flowers or fruit before it’s time to set them out, it’s best (although the act can break your heart) to pinch off the precocious buds. As the folks at Johnny’s Selected Seeds point out in their 1980 catalog, if such surgery isn’t done, the plants may remain stunted and produce only a few small, poor-quality fruits when they’re placed in the garden.

After the last frost, begin to harden off the plants. Omit a watering or two, and then place the seedlings (still in their containers) in a sheltered, semi-shaded place in the garden for three or four days . . . bringing the plants in at night. Then, for the following week or so, allow the plants to remain in a sheltered spot in the garden overnight. While the young vines are hardening off, you’ll have time to prepare the bed (if you didn’t do so the previous fall). Take a soil test, and adjust for a pH of 6 to 6.9 . . . adding lime if the soil is too acidic (the calcium will help prevent blossom-end rot, too) and sulfur if it’s too alkaline.

Tomatoes are particularly fond of organic matter, so try to incorporate large amounts of compost or well-rotted (not fresh) manure as you work the plot to a depth of ten inches. If your soil test indicated a need for fertilizer, remember that a low nitrogen mix is best: Look for a 5-10-10 blend.

Then, if you live in a region with a balmy spring and a scorching summer, place the transplants in compost-lined holes deep enough to cover each vine almost to its top set of leaves. Nip off the lower fronds, wrap a three-inch strip of newspaper around the stem as a cutworm collar (half above the soil line and half below), set the plant in the hole, fill and firm the soil, and water it well. The deep root run will be shielded from summer’s heat and dryness, and below ground moisture will always be available to the plant.

If, on the other hand, you live in a colder area, try the trench planting method advocated by Dick Raymond in his Down-to-Earth Vegetable Gardening Know-How (Garden Way, 1975). Dick suggests digging a three-inch-deep trench, placing a half inch layer of compost or aged manure in the bottom, and then laying the transplant (after pinching off all but the topmost cluster of leaves) on its side in the groove. Cover the stem with soil, propping up the tomato’s top with a little pillow of earth, and water it well. Mother Nature will soon have the plant growing straight and tall, while the roots that form along the stem will be basking in the sun’s warmth under their shallow earthen blanket.

No matter which system of planting you choose, you’ll still have to decide how–and if–you want to support your plants. If you’re raising determinate tomatoes, there’s little problem. The sturdy but compact growers hold their own heads up high, and little or no help is necessary (although sometimes a minimal two-foot cage is useful). Indeterminate plants can become huge, though, and-unless you’re willing to let the big vines sprawl (with the attendant waste of space and rotting fruit) you’ll probably choose either staking or cages as a method of support.

Staking starts easily but requires additional work later. Use an eight foot 2 x 2 for the prop, and drive it in next to the plant downwind from the prevailing breeze at transplanting time. That’s the easy part . . . now comes the work: pruning and tying up. The main stem must be tied to the pole. Use soft cloth or twine, or plastic tape . . . and tie the stalk loosely, of course, to avoid girdling (and killing) the plant. (One excellent scrounged tying material is old nylon stocking or pantyhose fabric . . . !t has enough give to avoid choking the vine.) Then, as suckers–or new branches–develop where the old limbs meet the stem, the new growth must be pinched out. Let a couple of leaves develop on the sucker, and then prune above the leaves . . . to better protect the fruit from the sun.

Caging the plants, on the other hand, requires more work up front . .. but virtually no maintenance later. The real labor is in making the cages, for which you should use large-meshed (five-inch or greater) concrete-reinforcing or hog wire. The ideal cage size seems to be two feet in diameter and five feet tall, so you’ll need to cut a 6′ 4″ length of five foot fencing to work with. Form the wire into a cylinder and crimp the ends to each other to ensure stability.

You can anchor the cage to the ground by using wooden stakes or wire attached to the bottom of the support . . . or you can remove the bottom layer of crosspieces and push the vertical prongs into the earth. That’s it! The plant will be contained and supported by the cage without any pruning (or other action) on your part. Now all you have to do is to keep the vines fed and watered and the bugs picked off . . . and to harvest, in the fullness of time, a bumper crop of succulent red tomatoes.

EDITOR’S NOTE: Ortho Publications has produced a beautifully illustrated and well written (if you ignore the pesticide bias) book entitled All About Tomatoes, which will answer just about any question you might have concerning the fruit.

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