Tomatoes are the top home garden crop for a reason, but they do have some trouble areas. Learn how to start tomatoes from seed at home and keep them growing well all season long!

About Growing Tomatoes Tomato plants are tender warm-season crops that love the sun and cannot bear frost. It’s important not to put plants in the ground too early. In most regions, the soil is not warm enough to plant tomatoes outdoors until late spring and early summer except in zone 10, where they are a fall and winter crop. See when to start tomatoes for your location.

Tomatoes take 60 days to more than 100 days to harvest, depending on the variety (see more about varieties below). Due to their relatively long growing season requirements (and late planting date), most gardeners plant small “starter plants” or transplants instead of seeds after the weather has warmed up in spring. Many gardeners purchase their transplants at a garden center or nursery but you can certainly grow you own from seed indoors.

A few guidelines on buying transplants: Choose young tomato plants from a reputable nursery.

Good starter plants are short and stocky with dark green color and straight, sturdy stems about the size of a pencil or thicker.

They should not have yellowing leaves, spots, or stress damage, nor have flowers or fruits already in progress.

Planting Select a site with full sun! In northern regions, 8 to 10 hours of direct sunlight are preferred. In southern regions, light afternoon shade (natural or applied, e.g., row covers) will help tomatoes to survive and thrive. Dig soil to about 1 foot deep and mix in aged manure and/or compost. Give it two weeks to break down before planting.

Also, choose a space where tomatoes (and members of their family, especially eggplants, peppers, and potatoes) have not grown in the previous couple of years. See tips on crop rotation.

When to Plant Tomatoes Tomatoes are long-season, heat-loving plants that won’t tolerate frost, so wait until the weather has warmed up in the spring. See our Planting Calendar for when to start tomatoes in your location.

If you are starting tomatoes from seed, sow indoors 6 weeks before the last expected spring frost date in your area. Sow seeds 1/2-inch deep in small trays. Plant seedlings outdoors about 2 weeks after that date or when temperatures stay in the mid-50 degree range both day and night. Learn more in our article on “Tomatoes From Seed the Easy Way” for more tips.

If you have a long enough growing season, it is also possible to direct-seed tomatoes in the garden soil (1/2-inch deep)—but not before the soil is at least 55°F. Note that 70°F soil is optimum for maximum germination within 5 days.

Hardening Off Tomatoes If you’re buying or growing the start plants, you’ll need to “harden off” the seedlings for a week before transplanting them in the ground. Set them outdoors in the shade for a few hours on the first day. Gradually increase this time each day to include some direct sunlight. Learn more about hardening off seedlings.

Tomato seedlings Transplanting Tomatoes Transplant your seedlings (or your nursery- grown plants) into the ground outdoors after all danger of frost has passed and the soil is at least 60°F. See our Planting Calendar for suggested transplanting dates.

Place tomato stakes or cages in the soil at planting. Staking and caging keep developing fruit off the ground (to avoid disease and pests) and also help the plant to stay upright. See instructions on how to build stakes, cages, and tomato supports.

Optional: When you transplant tomatoes, add a handful of organic tomato fertilizer or bone meal (a good source of phosphorus) to the planting hole. Do NOT apply high nitrogen fertilizers such as those recommended for lawns, as this will promote luxurious foliage but can delay flowering and fruiting.

When planting seedlings, pinch off a few of the lower leaves. Here are two ways to set seedlings in the soil: Place each root ball deep enough so that the bottom leaves are just above the surface of the soil. Roots will grow all along the plant’s stem underground. Plant seedlings 2 to 3 feet apart. Crowded plants will not get sufficient sun and the fruit may not ripen. Alternatively, lay long, leggy transplants on their sides in trenches 3 to 4 inches deep. Bury the stems up to the first set of true leaves. Roots will develop along the buried stem. If you plant this way, consider setting four tomato plants in compass-point positions (north, south, east, west). This formation enables you to fertilize and water the plants in the middle. Remember to allow enough space for the plants to spread out.

Water well to reduce shock to the roots.