Vegetables to Seed Start Indoors

Seed Starting IndoorsSnow on the ground. Heavy winter rain in the garden. Last average frost date weeks away. No problem. You can start the spring vegetable garden indoors.

If you know the average date of the last spring frost in your garden or region, you can make a schedule for starting vegetable crops indoors and get growing weeks before the outdoors temperatures warm. (Check at your local library or the county cooperative extension if you are unsure of the average last frost date.)

Here is a list of vegetables that are commonly started indoors and later transplanted to the garden:
Here are succession-cropping suggestions that might work in your region:

Crops  Tips for seed starting
Onions, leeks: bulb-forming leeks and sweet Spanish and Bermuda onions require a long growing season to reach maturity, so give them a good head start. Bunching onions are ready in 55 days, dry onions in 100 days; leeks in 130 days.
10 to 12 weeks: seed germinates best at 65°F, but will germinate at any temperature between 45° and 85°F. Start seed in the fall in warm-winter regions or where spring turns to summer quickly.
Early tomatoes: push the season with cold and cool weather tolerant varieties; early tomatoes reach maturity in as little as 55 days from transplanting into the garden.  10 to 12 weeks: tomatoes need plenty of time to develop strong root systems. Grow on seedlings indoors at 75°F day and 65°F night to as low as 50°F night to prepare for early transplanting. Protect seedlings when they go into the garden: hot caps, baskets, plastic or glass jugs. Warm garden soil with black plastic before transplanting.
Celery: start indoors for spring crop; seeds for fall or winter crop are usually sown outside in spring. Allow 5 to 6 months for plants to reach harvest from seed.  8 to 10 weeks: Frost resistant and can be set out while the weather is still cool. Do not expose seedlings to temperatures below 50°F for extended period or they may bolt.
Mid-season and late-season tomatoes: these tomatoes require from 70 to 110 days from transplanting to reach maturity.  6 to 8 weeks. Seed germinates in 8 to 10 days at 70°F. For a long season, plant several varieties with differing days to maturity.
Early peppers: reach maturity in 70 to 90 days after transplanting.  6 to 8 weeks: Grow on seedling at 65°F day and 55°F night. Set out transplants two weeks after the last frost when the soil has warmed; set in garden two to three weeks earlier if plants are protected by cloche or plastic tunnel.
Eggplant: reaches maturity in 90 to 125 days.  6 to 8 weeks: Seed germinates in 10 to 12 days at 70°F. Grow on seedling at 65°F day and 55°F night. Do not set transplants in the garden without protection until daily temperature stays above 65°F; set out earlier under hot caps or cloches, Use deep mulch to protect seedlings in garden from wind.
 All other peppers  4 to 6 weeks: Grow on seedling at 65°F day and 55°F night. Transplant to garden two weeks after the last frost.
Cabbage: transplant to the garden a week or two before the average last frost date allowing this cool-weather crop to reach maturity before warm weather arrives. Reaches maturity in 65 to 125 days.  4 to 6 weeks: germinates quickly at 70° to 75°F started indoors. Grow on seedlings at 65°F day and 55°F night. Frost resistant and can be set out while the weather is still cool but after the last severe freeze.
Cauliflower: transplant to the garden a week or two before the average last frost date allowing this cool-weather crop to reach maturity before warm weather arrives. Reaches maturity in 90 to 150 days.  4 to 6 weeks: germinates in 7 to 9 days at 70° to 75°F started indoors. Grow on seedlings at 65°F day and 55°F night. Frost resistant and can be set out while the weather is still cool. Spring crop must mature before hot weather; fall crop must mature before first fall frost.
Broccoli: transplant to the garden a week or two before the average last frost date allowing this cool-weather crop to reach maturity before warm weather arrives. Reaches maturity in 65 to 100 days.  4 to 6 weeks: germinates quickly at 70° to 75°F started indoors. Grow on seedling at 65°F day and 55°F night. Frost resistant and can be set out while the weather is still cool. For fall crop, sow seed in garden midsummer.
Head lettuce: unlike loose-leaf lettuce, head lettuce needs more time–80 to 90 days―in cool weather to form a firm head.  3 to 4 weeks: germinates in 6 to 8 days at 65°F. Great Lakes is a popular home garden head variety. If weather turns hot, heads will not form; start in fall in warm-winter regions.
Melons and cucumbers: these crops are transplanted to the garden small while there is less risk of disturbing their sensitive roots.  3 to 4 weeks: Time melon sowing so that plant is set outside when the soil temperature has risen to 50°F nights and near 80°F days. Cucumber seed germinates indoors in less than 3 days with bottom heat of 80°F; grow on seedlings at temperatures not less than 65°F. Set transplants in garden when melon and cucumber starts have no more than 4 leaves to avoid disturbing developing roots.