There are a few kinds of tomatoes that can be grown successfully indoors during the winter if you have a sunny window sill or can provide artificial light.
The ones grown outdoors during the summer are not suitable for growing indoors, even in a greenhouse. Tests at several agricultural stations have shown this to be true.
The big problem with growing tomatoes in the home is inadequate light. Tomato plants need at least 8 hours of good light daily to do well. They produce few flowers or fruit it they do not get enough light.
Use of fluorescent lamps can help only practical ones, for growing in the home are Pixie Hybrid, Small Fry Hybrid and Tiny Tim. Seed should be available at most seed stores and large garden centers.
Pixie is fast growing and can provide ripe fruit about 8 weeks after the plants come up. The plants grow 14 to 18 inches tall and bear a lot of bright scarlet, smooth, attractive tomatoes about the size of a billiard ball.
The tomatoes will not be quite as large as they would be if grown outdoors but they will ripen larger than cherry tomatoes and taste delicious.
Small Fry Hybrid also is early, 52 days, and produces large quantities of small, tasty, bright-red marble-size fruit of high quality. It won an All-America award. It gets to be 15 to 18 inches tall.
Tiny Tim grows about 15 inches tall and bears many cherry-size tomatoes, brilliant-scarlet and fine flavored.
You will need some pots or tin cans 6 to 8 inches in diameter. Use good rich potting soil. Be sure water drains readily from the bottom of the container.
Recent studies at the ornamentals laboratory of USDA's Agricultural Research Service, Beltsville, Md. suggest that fluorescent lights do a better job of producing healthy plants at lower cost than do incandescent plant growth lights.
The lights tested included a fluorescent type that sells for about $15 and three incandescent types. The incandescent lights included a flood lamp that sells for about $2, a special growth lamp that is basically the same but sells for about $5, and a cool lamp with a filter that sells for $8 to $10.
Petunias grown under fluorescent lights look like those grown under greenhouse conditions: they are compact and luxuriant, with deep green foliage. Although plants differed somewhat depending on the kind of light used, all were long and stringy.
According to Dr. Henry M. Cathey, chief of the ornamentals laboratory, light from an incandescent source is in the red range, which promotes internode lengthening and eventually turns all plants into climbing vines.
Such finds do not suggest that incandescent light should not be used for indoor plants, he said. Incandescent lights, such as hanging floor lamps can be used in decorative arrangements to supplement light from a window, but good natural light must be available also.
Fluorescent lights, regardless of color, can be used to promote growth of most plants indoors.
Growing tomatoes in a greenhouse is quite different from growing them in the field. A variety is needed that yields well, coupled with resistance to the major diseases that occur under greenhouse conditions.
Rate of fertilization is important in greenhouse gardening, especially with nitrogen. With too much, the plants become overly vegetated, and bear poor-quality fruit. With too little, stunting occurs, especially if the nitrogen is applied toward the end of the season.