If you’re a gardener, thoughts turn to germinating tomato (Lycopersicon esculentum) seeds when January rolls around, because tomatoes can be started from seed indoors about six to eight weeks before the last frost date. As mentioned by North Carolina State University, tomato seeds germinate with or without light, so there is no need to place them in a sunny window, but, once seeds sprout, they don’t need lots of light to grow and eventually become vigorous.

Sowing Seeds

Since seeds don’t need light to germinate, you can germinate them everywhere, even inside a dark cabinet if you like. Start seeds by sterilizing a seed tray by dropping it for 10 minutes in a solution of 1 cup bleach and 9 cups water. Thoroughly rinse and dry the tray prior to filling it with seed-starting mix that contains fertilizer, available from garden centres. Fill within 1/4 inch from the lip, then tamp down the ground marginally to remove air pockets. Water the mix so that it’s wet all of the way through, but never soggy. Sow the seeds by poking a hole in every tray cell, with your finger, 1/4-inch deep into the soil. Drop in one seed per hole and cover with enough dirt so that it’s level. Add enough water to moisten the seed and added dirt, and replace the tray’s plastic cover to prevent moisture loss.

Maintaining Seeds Warm

For seeds to germinate, the land has to be kept between 70 and 80 degrees Fahrenheit. You can place them in a warm place on your house or place the tray on a heating mat. A heat mat keeps dirt at about 70 degrees Fahrenheit. Generally, seeds germinate in seven to ten days. While you’re waiting for the seeds to sprout, keep the soil moist. Use your finger to see if the very best 1/4 inch is dry, if so, add enough water to moisten the soil. Don’t overwater. Soggy seeds rot and will not germinate.

Lighting Seeds

Once seeds have sprouted, seedlings prefer temperatures around 65 F. You can place them at a south-facing window, but because sun in winter is not as extreme as in summertime, tomato sprouts may develop into spindly, weak seedlings if only given natural light. The University of California Cooperative Extension explains that you can strengthen seedlings by supplying glowing light for an additional three or even four hours daily, for a total of 16 to 18 hours of light daily. Put recently sprouted seeds under 2 40-watt fluorescent bulbs hung around 4 inches above the plants, or another kind of increase light. Don’t use incandescent light bulbs as they are hot and scorch plants. As the plants develop, adjust the lights upward. Plants also need a period of dark, so switch off the lights daily. Don’t develop seedlings on a heat mat, and continue to water when the soil mix dries out. Supplemental fertilizer isn’t needed until the seedlings are transplanted outdoors.

Transplanting Spindly Seedlings

Should you attempt growing tomato seedlings in a sunny window and the plants become leggy and weak, don’t despair. Just plant them at the ground deeper than you’d normally, at a 45-degree angle with only the top two or three sets of leaves sticking out. Before planting, remove the lower leaves from the stem of the plant. Cover the seedling so that the dirt is level. Water thoroughly and at time new roots will form along the stem, where you removed the leaves, creating a healthy, vigorous plant.

See related