indoor seed starting - lettuce

6 vegetable seeds to plant in February

February is the right time to start many cool-season vegetables indoors and, in milder climates, to sow a few crops directly outside. In USDA Zone 8 and warmer, garden beds may be workable by mid to late February. In colder regions, including USDA Zone 3 to 7, indoor seed starting is the practical way to gain time before the last frost date. If soil can be worked and daytime temperatures stay above 40°F (4°C), some crops can go straight into the ground. For most gardeners, however, February is about trays, lights, and planning.

Starting early only works when timing matches plant biology. Cool-season vegetables tolerate light frost and grow well at 45°F to 65°F (7°C to 18°C). Warm-season crops need sustained warmth and should not be rushed.

February planting chart by zone: start indoors or direct sow

Use this chart to see what to sow this month in your zone. The third column shows how many weeks February sits before your average last frost. Seed timing is counted back from that date. The frost ranges are broad zone averages from Garden Design. Crop timing comes from the University of New Hampshire Extension planting fact sheet.

USDA zoneAverage last frostFebruary is this many weeks before last frostStart indoors in FebruaryDirect sow or plant out in February
3May 1 to 169 to 15Onions, leeks, and parsley. Celery late in the month.Nothing yet. Wait for the soil to thaw.
4April 24 to May 128 to 14Onions, leeks, parsley, and celery.Nothing yet.
5April 7 to 306 to 13Onions, leeks, parsley, and celery early in the month. Cabbage, kale, spinach, and lettuce late in the month.Nothing yet in most years.
6April 1 to 215 to 11Onions and leeks in the first days of the month (if not started in January). Celery early in the month. Broccoli, cabbage, kale, lettuce, and spinach from mid-month. Peppers and eggplant late in the month.Peas, once the soil thaws and can be worked.
7March 22 to April 33 to 9Broccoli, cabbage, kale, lettuce, and spinach early in the month. Peppers and eggplant mid-month. Tomatoes late in the month.Peas once the soil thaws. Radishes and turnips late in the month.
8March 13 to 282 to 8Peppers, eggplant, and tomatoes early in the month.Peas, radishes, turnips, and Swiss chard. Beets once the soil reaches 45°F (7°C). Set out onion, cabbage, and kale transplants.
9February 6 to 280 (last frost falls this month)Too late for most indoor starts.Set out broccoli, cabbage, and lettuce transplants early in the month. Sow radishes, beets, and Swiss chard. Plant seed potatoes 1 to 2 weeks before your last frost.

Treat the zone column as a starting point. USDA hardiness zones are based on the coldest winter temperature, not on frost dates. Two gardens in the same zone can have last frosts weeks apart. For your own date, check the NOAA map of the average last spring freeze. It uses 1991 to 2020 climate data and marks the date when the chance of a 32°F (0°C) freeze drops below 50 percent. A frost after that date is still possible.

How many weeks before last frost to start each crop

Each sowing window below combines two numbers from the UNH Extension fact sheet: the weeks from seed to transplant, and the date the plant can safely go outside. Onions take 8 to 10 weeks from seed to transplant and can go out 4 weeks before last frost. So onion seed goes in 12 to 14 weeks before last frost. Peppers take 8 to 10 weeks but go out 2 weeks after last frost, so they start 6 to 8 weeks before it.

CropSeed to transplantSafe to set outSow indoors (weeks before last frost)
Onion, leek8 to 10 weeks4 weeks before last frost12 to 14
Parsley9 to 10 weeks2 to 3 weeks before11 to 13
Celery10 to 12 weeksAfter last frost10 to 12
Cabbage, kale4 to 6 weeks4 weeks before8 to 10
Spinach4 to 6 weeks3 to 6 weeks before7 to 12
Lettuce4 to 5 weeks3 to 4 weeks before7 to 9
Broccoli4 to 6 weeks2 to 4 weeks before6 to 10 (varies by source)
Pepper8 to 10 weeks2 weeks after6 to 8
Eggplant8 to 10 weeks2 to 3 weeks after6 to 8 (varies by source)
Tomato6 to 8 weeks1 to 2 weeks after4 to 7 (varies by source)

Cold-climate note for zones 3 to 6

In zones 3 to 6, February is mostly an indoor month. The University of Minnesota Extension seed calendar puts onions and leeks in early February and celery in mid-February. It holds broccoli, Brussels sprouts, cabbage, cauliflower, and head lettuce until early March. Peppers and eggplant wait until mid-March, and tomatoes until early April.

Hold back warm-season crops in cold zones. Tomatoes need only 6 to 8 weeks from seed to transplant. Sown in mid-February in zone 4, they would wait indoors for 11 to 14 weeks before it is safe to plant them out.

I grow in raised beds in Armstrong, in the North Okanagan of British Columbia (about USDA zone 5b to 6a). That puts my garden in the zone 5 and 6 rows of the chart. Canadian gardeners can use the same weeks-before-frost math with their own local frost date.

Vegetable seed packets on a marble countertop

1. Peas

Peas are among the earliest vegetables to plant. Garden peas germinate in soil as cool as 40°F (4°C) and prefer air temperatures between 50°F and 70°F (10°C to 21°C). In USDA Zone 6 and warmer, they are often direct sown from February 15 to March 15 if the soil is workable. In colder climates, starting peas indoors in cell packs gives a two to three week head start.

Use a well-drained soil rich in organic matter with a slightly acidic to neutral pH around 6.0 to 7.0. Sow seeds about 1 inch deep. If starting indoors, transplant while seedlings are still small to avoid root disturbance. Provide support at planting time. Peas grow quickly in cool conditions and decline once daytime temperatures regularly exceed 75°F (24°C).

2. Radishes

Radishes are reliable for early sowing and mature in as little as 21 to 30 days. In warm winter regions, they can be direct seeded in February. They germinate at 45°F to 85°F (7°C to 29°C), with best root quality produced at 50°F to 65°F (10°C to 18°C).

Plant seed ½ inch deep in loose soil free of stones. Thin early to prevent crowding. Rapid growth depends on steady moisture. If growth stalls due to cold or drought, roots become woody or overly spicy. Because of their speed, radishes are useful for filling empty tray space indoors or for succession sowing every two weeks.

3. Spinach

Spinach thrives in cool conditions and tolerates light frost. Seeds germinate in soil temperatures from 40°F to 75°F (4°C to 24°C), with optimal growth at 50°F to 60°F (10°C to 16°C). February sowing works indoors under lights or outdoors in mild climates.

Use free-draining soil high in organic matter with a pH near 6.5 to 7.0. Keep seedlings cool once they emerge. Warm indoor rooms above 70°F (21°C) combined with low light cause stretching. Position lights 2 to 3 inches above seedlings and provide 14 to 16 hours of light daily. Harvest outer leaves early to extend production.

4. Lettuce

Lettuce germinates at 40°F to 75°F (4°C to 24°C) and prefers growing temperatures between 45°F and 65°F (7°C to 18°C). It is well suited to February seed starting. Seeds are small and should be sown shallowly, barely covered with mix.

Seedlings can be trimmed lightly if they outgrow their trays before transplanting. Move plants outdoors once soil is workable and nighttime temperatures remain above 25°F (-4°C). Harden off gradually over 7 days before planting into the garden. Loose-leaf varieties adapt especially well to early sowing.

5. Broccoli

Broccoli and other brassicas benefit from early indoor sowing. Start seeds 6 to 10 weeks before your last expected frost date. The range varies by source. The UNH Extension and Cornell timings fall in this window, while Illinois Extension gives a shorter 4 to 6 weeks. Germination occurs at 45°F to 85°F (7°C to 29°C), but seedlings grow best at 60°F to 70°F (16°C to 21°C).

Use fertile, well-drained soil with consistent moisture. Provide strong light to prevent leggy stems. Cabbage, cauliflower, kale, and Brussels sprouts grow the same way, but cabbage and kale start a little earlier (see the table above). Transplant broccoli outdoors 2 to 4 weeks before the last frost once plants have 4 to 6 true leaves. Protect from severe freezes below 20°F (-6°C).

6. Eggplant

Eggplant requires warmth and a long growing season. Start seeds indoors 6 to 8 weeks before your last frost date. The range varies by source: Clemson Extension says 8 weeks, and the Cornell growing guide says about 6. Germination is best at 75°F to 85°F (24°C to 29°C). Use bottom heat if room temperatures are cool.

Sow seeds ¼ inch deep and keep soil evenly moist. After seedlings develop 4 to 6 true leaves, transplant into larger containers. Maintain temperatures above 70°F (21°C) during the day and at least 60°F (16°C) at night for steady growth.

Move plants outdoors only after frost danger has passed and nighttime temperatures remain above 50°F (10°C). Harden off gradually over 7 to 10 days. Space plants in full sun in well-drained soil. Harvest fruits when glossy and firm. Most varieties mature 70 to 85 days after transplanting.

Avoid planting these vegetables in February

It is too early to start tomatoes in most climates. Tomato seedlings grow quickly and become difficult to manage if started too soon. Start tomato seeds indoors 4 to 7 weeks before your last frost date. The range varies by source: Clemson Extension says 6 weeks, and the UNH Extension timing works out to 4 to 7. In many regions, that means March or early April.

Beans, cucumbers, basil, and squash family crops also prefer warmer soil and should wait until closer to planting time. These plants resent root disturbance and grow rapidly once sown, making early February starts impractical unless you have greenhouse space with consistent warmth above 65°F (18°C).

Tips for seed germination

Use fresh, properly stored seed. Most vegetable seed remains viable for two to five years if kept dry and cool. Check packet dates before planting.

Plant at the correct depth, usually about twice the seed diameter. Firm the soil gently to ensure seed to soil contact.

Maintain even moisture without saturation. Overwatering limits oxygen and encourages rot. A spray bottle or bottom watering tray reduces disturbance.

Provide the right temperature. Many seeds germinate well around 70°F (21°C). Cool-season crops tolerate lower temperatures, while warm-season crops benefit from bottom heat.

Tips for growing vegetables after germination

Provide strong light immediately after emergence. Seedlings need 12 to 16 hours of bright light daily. Position grow lights 2 to 3 inches above plant tops and adjust as they grow.

Water consistently but allow the surface to dry slightly between waterings. Good drainage prevents root disease.

Begin light feeding once true leaves appear. A diluted balanced fertilizer applied every two weeks supports steady growth without excess stretch.

Starting seeds indoors during the winter

Indoor seed starting extends the growing season in cold climates. Basic supplies include seeds, containers with drainage, sterile seed starting mix, grow lights, heat mats, and a watering can with a fine rose.

Fill containers at least 2 to 3 inches deep with pre-moistened mix. Sow according to packet depth instructions. Keep trays warm until germination, then move immediately under lights. Maintain gentle air circulation with a small fan to strengthen stems and reduce fungal issues.

Harden off seedlings before transplanting. Place plants outdoors in a sheltered area for a few hours on day one, increasing exposure gradually over a week. This reduces transplant shock and improves survival.

Additional info for starting veggie seeds in February

Cold frames provide an intermediate step between indoor and outdoor growing. They protect seedlings from wind and frost while allowing natural light. Early carrots, onions, Brussels sprouts, and hardy greens can be started this way in milder regions.

In cooler climates, heated greenhouses or bright windowsills allow gardeners to grow lettuce, spinach, kale, and herbs through late winter. In warmer regions, direct sowing becomes possible once frost risk declines and soil warms. Always match planting dates to your local last frost date and average soil temperature.

Greenhouses for year-round growing

Greenhouses create controlled environments for consistent production. By managing temperature, humidity, and light, growers can sow earlier and harvest longer. Supplemental heat keeps winter temperatures above crop minimums, while ventilation prevents overheating on sunny days.

Stable temperatures are essential. Large swings between day and night slow growth and stress plants. Heating systems should match climate demands and include backup options in cold regions. Proper ventilation and spacing reduce pest and disease pressure.

Cold frames for season extension

Cold frames are smaller, unheated structures used to extend the season for hardy crops. They capture solar warmth during the day and retain heat overnight. Gardeners use them to start seeds early, protect transplants, and harden off seedlings.

Vent on mild days to prevent overheating above 75°F (24°C). Close covers before sunset to trap warmth. With proper management, cold frames provide several extra weeks of productive growing time in late winter and early spring.

Seed companies I like

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Mary Jane Howie - Home for the Harvest

Home for the Harvest

Hi, I’m Mary Jane! I’m a Master Gardener and the creator of Home for the Harvest, where I share simple, science-based gardening tips for growing a beautiful and productive garden.


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