Plant tomatoes after the last frost date in your area, in soil or containers with full sun and good drainage

Tomato plants need warmth to grow, so timing matters more than most garden tasks. Plant them outdoors only after the last frost date has passed — frost will kill them. You can find your local frost date by searching "[your city] last frost date" or checking with your county extension office. In most of the United States, this falls between mid-April and late May, but it varies by region.

Tomatoes also need at least six to eight hours of direct sunlight daily and soil that drains water instead of holding it. If your garden stays wet or shaded, containers on a sunny patio work just as well. The soil itself should be loose and rich in organic matter — either garden soil mixed with compost, or a bagged potting mix if you are using containers.

Key Takeaways

  • Wait until after your area's last frost date to plant tomatoes outdoors, or they will die from cold.
  • Choose a spot with at least six to eight hours of direct sun daily, or use containers you can move to sunlight.
  • Dig a hole deeper than the root ball and bury the stem partway up the plant — tomatoes will grow roots along the buried stem.
  • Water deeply at the soil level right after planting and keep the soil consistently moist but not waterlogged for the first few weeks.
  • Space plants two to three feet apart in the ground or use one plant per five-gallon container to give roots room to spread.

Prepare the soil or container before planting

If you are planting in the ground, loosen the soil to a depth of at least eight inches and mix in two to three inches of compost or aged manure. Tomatoes are heavy feeders and need rich soil to produce well. If your garden soil is compacted or poor, this step makes a real difference in how many tomatoes you get.

For containers, use a potting mix — not garden soil, which compacts in pots and blocks drainage. A five-gallon container holds one tomato plant comfortably; a ten-gallon container can hold two if they are determinate varieties (bush types that stay compact). Fill the container to within two inches of the rim so water does not run straight off the top.

Dig the hole and position the plant

Dig a hole slightly wider than the root ball and deeper than it is tall. This is the key step that makes tomato planting different from most other plants: you will bury the stem partway up the plant, not just to the soil line. Tomatoes grow roots all along their buried stem, which gives them a stronger foundation and access to more water and nutrients deeper in the soil.

Remove the tomato plant from its pot and gently loosen the roots with your fingers. If the roots are tightly wound in a circle, make three or four shallow cuts down the sides of the root ball to encourage them to spread outward instead of continuing to circle. Place the plant in the hole so that the lowest leaves are just above the soil surface, then fill the hole and press the soil gently but firmly around the stem.

Water when ready and establish a routine

Water deeply right after planting so the soil settles around the roots and removes air pockets. The soil should be moist to a depth of six inches. For the first two to three weeks, keep the soil consistently moist — not soggy, but not dry either. This helps the plant establish roots in its new location.

After the plant is established, water deeply but less often. Tomatoes prefer one deep watering per week to frequent shallow watering. Water at the soil level, not on the leaves, because wet foliage invites fungal disease. In very hot weather or in containers, you may need to water twice a week.

Space plants to allow air circulation and growth

In the ground, space tomato plants two to three feet apart, depending on the variety. Determinate (bush) varieties can be closer; indeterminate (vining) varieties need more room. Check the plant label or seed packet for the specific spacing recommendation for the variety you are growing.

Spacing matters because it allows air to move between plants, which reduces disease. It also gives each plant's roots room to spread without competing with neighbors. If you are planting in containers, one plant per five-gallon pot is the standard — do not crowd multiple plants into one small container.

Support tall or vining varieties with stakes or cages

Indeterminate tomatoes (the kind that grow tall and produce all season) need support so the stems do not break under the weight of fruit. Install a stake or cage at planting time, before the roots spread, so you do not damage them later. A wooden stake four to six feet tall works well for staking; a wire cage works for bushier plants.

Tie the main stem loosely to the stake with soft twine or cloth strips as the plant grows. Do not tie it tight — the stem needs room to expand. Determinate varieties (bush types) may not need support, but many gardeners use a cage anyway to keep fruit off the ground and improve air circulation.

Harden off seedlings before planting outside

If you started tomatoes from seed indoors, they need a transition period before moving to the garden. This process, called hardening off, gradually exposes the tender seedlings to outdoor sun, wind, and temperature changes. Without it, they will wilt or stop growing when you plant them.

Start by placing seedlings in a sheltered, shaded outdoor spot for one to two hours. Each day, increase their time outside and gradually move them into more direct sun over seven to ten days. By the end of the period, they should spend a full day and night outside before you plant them in the garden. This takes patience but prevents transplant shock and gives you stronger plants.

Frequently Asked Questions

Can I plant tomatoes deeper than the lowest leaves?

Yes — this is actually recommended. Bury the stem up to the lowest set of leaves or even higher. Tomatoes will grow roots along the buried portion of the stem, creating a stronger root system that reaches deeper into the soil for water and nutrients during dry spells.

What if my area gets frost after I plant?

If an unexpected frost is forecast after planting, cover plants with blankets, cardboard, or frost cloth overnight. Remove the cover during the day so the plant gets sun. If the plant is already in the ground and frost damage occurs, wait a few days — sometimes the plant will recover and send out new growth from undamaged stems below the frost line.

How much sun do tomatoes really need?

Tomatoes need at least six to eight hours of direct sun daily to produce well. Less sun means fewer flowers and fewer tomatoes. If your garden is shaded, containers let you move plants to a sunnier spot — a south-facing patio or driveway usually works.

Can I plant tomatoes in the same spot every year?

It is better not to. Tomatoes are susceptible to soil-borne diseases that build up over time in the same location. Rotate tomatoes to a different bed each year, or use fresh potting mix in containers. If you must plant in the same spot, replace the top six inches of soil with compost or new garden soil.

Should I remove the bottom leaves before planting?

No — leave all leaves on at planting time. The plant needs them to photosynthesize and establish roots. Once the plant is growing and producing fruit, you can remove lower leaves if they touch the ground or show disease, but at planting time, keep everything the plant has.