June 13, 2013
Q. How soon can I plant tomato seeds indoors under a grow light, and how many hours of light do they need?

A. There is nothing better than to pick a ripe tomato from your own garden. Tomatoes from seed need to be started at least six to eight weeks before your last frost date. By that time, the soil will be warm enough to get them growing. Sow seeds in moistened soil that is labeled for seedlings. Provide heat, if possible, to the bottom of the container to begin the germination. Follow the instructions on the seed packet as to seed depth. Place a plastic covering over them. At the first sign of the cotyledon pushing through the soil, remove the cover and move to your growing lights. Place your seedlings two to three inches below the light and raise them as the plants begin to grow taller. Turn the lights on in morning and off at night, to replicate a normal pattern of daylight. Keep the temperature cool, as they will grow too quickly and become spindly. As the plants become larger and have more leaves on them, replant them in a larger container. A couple of weeks before planting, make sure you take the seedlings outside in a sheltered place to harden them off (exposing them to the outside). Keep out of the wind and harsh hot sun. Hope this information helps.

Valerie E. Liney,
Lake Simcoe South Master Gardener