Plant tomatoes after your last spring frost, when soil reaches 60°F

The single most important date for tomatoes is your area's last spring frost date. Tomato plants die in frost, so you cannot safely plant them outdoors until that date has passed. You can find your frost date by searching "[your city] last frost date" or by checking the USDA Plant Hardiness Zone Map, which lists frost dates by region.

Even after the frost danger is gone, soil temperature matters. Tomato seeds and seedlings grow slowly in cold soil and may rot before they sprout. Wait until soil reaches at least 60°F before planting seeds directly in the ground. If you are transplanting seedlings (small plants started indoors), soil should ideally be 65°F or warmer for faster growth. You can measure soil temperature with a straightforward soil thermometer from any garden center.

In most of the United States, this means planting tomatoes between late April and late May. In warmer regions like southern Florida or southern California, you may plant in February or March. In cooler areas like the northern Midwest or New England, you may not plant until June. The frost date is the hard boundary; soil temperature is the comfort zone.

Key Takeaways

  • Plant tomatoes outdoors only after your last spring frost date has passed, which varies by region but falls between late April and late May for most of the country.
  • Soil temperature should reach at least 60°F before planting seeds, and 65°F or warmer for transplanting seedlings, because cold soil slows growth and causes rot.
  • Start seeds indoors 6 to 8 weeks before your frost date if you want mature plants ready to transplant on planting day.
  • Harvest tomatoes when they are fully colored but still slightly firm, usually 60 to 85 days after transplanting, depending on the variety.
  • In hot climates, plant a second crop in late summer for a fall harvest, since tomatoes stop setting fruit when temperatures exceed 90°F consistently.

Starting seeds indoors versus buying transplants

You have two paths: start seeds indoors yourself, or buy seedlings from a nursery and transplant them. Starting seeds indoors gives you more variety choices and costs less per plant, but requires grow lights and takes 6 to 8 weeks of care before planting day. Buying transplants is faster and requires no equipment, but limits you to whatever varieties the nursery stocks.

If you start seeds indoors, count backward from your frost date. Sow seeds 6 to 8 weeks before that date. For example, if your frost date is May 15, sow seeds indoors around March 20 to April 1. Seeds need warmth (70°F to 80°F), moisture, and light to sprout and grow into sturdy plants. Without grow lights, seedlings become tall and spindly and do not transplant well.

If you buy transplants, choose stocky plants with thick stems and dark green leaves. Avoid plants that are already flowering or have fruit, because they have used energy on reproduction instead of root growth and will not establish as well in the ground. Plant them as soon as you bring them home, or harden them off first by setting them outside in shade for a few hours each day for 3 to 5 days, gradually moving them into sunlight. This acclimates them to outdoor conditions and prevents transplant shock.

Timing for different tomato types

Determinate tomatoes (bush types that grow to a fixed size) mature faster than indeterminate types and produce most of their fruit in a short window, usually 2 to 3 weeks. Plant them all at once if you want a large harvest for canning or sauce-making. Indeterminate tomatoes (vining types that grow continuously) produce fruit steadily from mid-summer until frost. They take longer to start producing but keep going for months.

If you want a continuous harvest of fresh tomatoes throughout the season, plant indeterminate varieties. If you want a big harvest at once for cooking and preserving, choose determinate varieties. You can also plant both: determinate varieties for a main harvest, and indeterminate varieties for eating fresh later in the season.

Cherry and grape tomatoes are almost always indeterminate and produce heavily once they start. Large slicing tomatoes vary by variety. Check the seed packet or plant label to see whether the variety is determinate or indeterminate, and how many days it takes to mature.

Harvesting tomatoes at the right stage

Tomatoes are ready to harvest when they are fully colored but still slightly firm to the touch. A ripe tomato should give a little when you squeeze it gently, but should not be mushy. The color depends on the variety: red tomatoes are ripe when deep red all over, pink varieties when pink throughout, and yellow or orange varieties when uniformly colored.

Most tomato varieties produce fruit 60 to 85 days after you transplant them into the garden. Check the seed packet or plant label for the specific variety's days to maturity. Start checking plants around that time frame. Once tomatoes begin ripening, check every 2 to 3 days, because ripe tomatoes soften quickly and attract pests.

You can pick tomatoes at the "breaker stage"—when they show the first blush of color but are not yet fully ripe—and let them finish ripening on the counter indoors. This is useful if you have many ripe tomatoes at once, or if you want to protect them from birds or insects. Tomatoes picked at the breaker stage will ripen fully indoors in 3 to 5 days at room temperature.

Planting a second crop in hot climates

In areas where summer temperatures regularly exceed 90°F, tomato plants stop setting new fruit even though they keep growing. This happens in much of the South and Southwest. To get a fall harvest, plant a second crop in late summer, around 8 to 10 weeks before your first fall frost date.

For example, if your first fall frost is October 15, count back 8 to 10 weeks and plant seeds or transplants around mid-August. These plants will grow through the cooler fall weather and produce fruit as temperatures drop back below 90°F. Fall tomatoes often taste better than summer ones because they ripen slowly in cooler weather.

Start fall-crop seeds indoors in late June or early July, or buy transplants in late July or August. Transplants are often easier to find in late summer than seeds, since nurseries stock them for fall planting. Water fall-crop plants consistently, because late-summer heat can dry soil quickly even as air temperatures begin to cool.

Protecting plants from late and early frosts

If an unexpected frost is forecast after you have already planted, cover plants with blankets, burlap, or frost cloth to trap heat and protect them. Drape the cover loosely so it does not touch the leaves, and remove it the next morning when temperatures rise. A single frost cloth or blanket can save plants that would otherwise die.

At the end of the season, when the first fall frost approaches, you can extend the harvest by covering plants on frost nights. Once a hard frost kills the foliage, pick any remaining tomatoes—even green ones—and bring them indoors to ripen. Green tomatoes will ripen on a sunny windowsill or in a paper bag with a ripe banana or apple, which releases ethylene gas and speeds ripening.

Frequently Asked Questions

Can I plant tomatoes before the last frost date if I use row covers?

Row covers slow frost damage but do not prevent it entirely. If temperatures drop below 32°F, plants under row covers will still freeze. It is safer to wait until after the frost date, then use row covers only if an unexpected late frost is forecast.

What if my soil is still cold but the frost date has passed?

Wait a week or two for soil to warm up, or warm it yourself by laying black plastic or landscape fabric over the planting area for a few days before planting. Cold soil slows growth and increases the risk of root rot, so the extra wait is worth it.

How long do tomatoes take to grow from seed to harvest?

From seed to harvest takes about 70 to 100 days total, depending on the variety. This includes 6 to 8 weeks indoors for seedlings, plus 60 to 85 days in the garden from transplant to ripe fruit. Starting with transplants cuts the timeline to 60 to 85 days from planting day.

Can I harvest tomatoes before they are fully ripe?

Yes. Tomatoes picked at the breaker stage (first blush of color) will ripen fully indoors in 3 to 5 days at room temperature. This is useful if you have many ripe tomatoes at once, or if you want to protect them from pests or birds.

What should I do with green tomatoes at the end of the season?

Pick them before the first hard frost and bring them indoors. They will ripen on a sunny windowsill or in a paper bag with a ripe banana or apple. Ripening takes 1 to 3 weeks depending on how mature the green tomato was when picked.