Plant tomatoes in spring after the last frost, in a spot that gets at least six to eight hours of direct sun each day

Tomatoes need warmth to grow. Plant them outdoors only after the soil has warmed to at least 60°F and nighttime temperatures stay above 50°F — usually four to six weeks after your area's last spring frost. You can find your local frost date by searching "[your city] last frost date" or asking at a local garden center or cooperative extension office.

Choose a location where tomatoes receive six to eight hours of direct sunlight daily. More sun produces more fruit and reduces disease. Avoid spots where water pools after rain, since soggy soil causes root rot and fungal problems.

Key Takeaways

  • Wait until soil reaches 60°F and nighttime temperatures stay above 50°F before planting, which is usually four to six weeks after your area's last frost date.
  • Plant in a spot with six to eight hours of direct sun and soil that drains well — not in a low spot where water collects.
  • Dig a hole deeper than the root ball, bury the stem up to the first true leaves, and space plants 24 to 36 inches apart depending on variety.
  • Water deeply at the soil level once or twice weekly rather than daily, and add mulch around the base to retain moisture and prevent disease.
  • Stake or cage indeterminate varieties (which grow tall) at planting time; determinate varieties (bush types) need less support.

Prepare the soil before you dig

Tomatoes grow best in soil that is loose, drains well, and holds some organic matter. Before planting, work compost, aged manure, or peat moss into the top 8 to 10 inches of soil. This improves drainage and gives roots room to spread. If your soil is heavy clay, add extra compost — at least 2 to 3 inches worked in — so water does not sit around the roots.

You can also add a balanced fertilizer (such as a 10-10-10 formula) or a fertilizer made for tomatoes when you prepare the bed. Follow the package directions for how much to use based on your bed size. If you prefer not to add fertilizer at planting, you can feed the plant later once it starts flowering.

Dig the hole and position the plant

Dig a hole slightly deeper and wider than the root ball of your seedling. Tomato plants have a useful trait: they can grow roots all along their buried stem. This means you can plant the seedling deeper than it was growing in its pot — even up to the first set of true leaves. Burying more of the stem creates a stronger root system.

Gently remove the seedling from its pot and loosen the roots with your fingers. Place it in the hole so the soil line on the stem is at or slightly below ground level. If the seedling is tall and leggy, you can lay it in the hole at an angle; the buried stem will straighten up and develop roots. Backfill with soil and press gently to remove air pockets.

Space plants the right distance apart

Spacing depends on the variety. Determinate tomatoes (bush types that stay compact) can be planted 24 inches apart. Indeterminate tomatoes (vining types that grow tall all season) need 30 to 36 inches between plants. Wider spacing improves air circulation, which reduces fungal diseases like early blight and powdery mildew.

If you are planting in rows, space rows 36 to 48 inches apart so you have room to walk and harvest. Crowded plants compete for water and nutrients, and poor air flow traps moisture on leaves where disease starts.

Install support before the plant grows large

Indeterminate varieties need a stake, cage, or trellis to keep fruit off the ground and improve air circulation. Install the support at planting time, before the roots spread — driving a stake into the soil later can damage roots and shock the plant. A sturdy cage or stake should be at least 5 to 6 feet tall for indeterminate types.

Determinate varieties are bushier and more compact, so they often do fine with a shorter cage or no support at all, though a cage still helps keep fruit clean and accessible. Tie the main stem loosely to the support with soft ties or strips of cloth as the plant grows; do not tie it so tight that you cut into the stem.

Water deeply and mulch the soil surface

Water the newly planted seedling thoroughly so the soil settles around the roots. After that, water deeply once or twice per week rather than daily. Deep watering encourages roots to grow down into the soil; frequent shallow watering keeps roots near the surface where they dry out quickly. Water at the soil level, not on the leaves, to keep foliage dry and prevent fungal disease.

Spread 2 to 3 inches of mulch (shredded bark, straw, or wood chips) around the base of each plant, keeping it a few inches away from the stem. Mulch keeps soil temperature steady, reduces water loss, and prevents soil from splashing onto leaves during rain — which spreads disease spores.

Monitor for common problems in the first weeks

Young transplants sometimes wilt in the first few days after planting, especially if the weather is hot or windy. This is transplant shock and usually passes within a week. Water well and provide afternoon shade with a cloth or cardboard if temperatures exceed 85°F for the first few days.

Watch for pests like hornworms and aphids, and for early signs of disease like yellow leaves or dark spots. Pinch off affected leaves and remove pests by hand if you see only a few. Once the plant is established and growing, it becomes more resilient.

Frequently Asked Questions

Can I plant tomatoes in the same spot every year?

No. Tomatoes are prone to soil-borne diseases that build up over time. Rotate tomatoes to a different bed each year, or at least wait two to three years before planting tomatoes in the same spot again. This breaks the disease cycle.

What if my seedling is very tall and spindly?

Bury it deeper than normal — even up to the first true leaves. The buried stem will develop roots and create a stronger plant. You can also lay it in the hole at an angle; it will straighten up as it grows.

How do I know if my soil drains well?

Dig a hole about 12 inches deep, fill it with water, and watch how fast it drains. If water is gone within a few hours, drainage is good. If it sits for more than a day, add compost or peat moss to improve drainage before planting.

Should I remove the lower leaves once the plant is growing?

Once the plant is established and flowering, you can remove the lowest leaves to improve air circulation and reduce disease. Wait until the plant is at least a foot tall and has flowers forming. Remove only a few leaves at a time so the plant can still photosynthesize.

What if I plant too early and frost is forecast?

Cover plants with cloth, newspaper, or a frost blanket the night before frost is expected. Remove the cover during the day so the plant gets sun. If frost kills the above-ground part, the plant may regrow from the roots, though it will set back several weeks.