How to grow Tomato

Where to plant

Give tomatoes the sunniest spot you have, ideally 6 to 8 hours or more of direct sun, in rich, well-drained soil with plenty of compost and a pH of about 6.2 to 6.8. Leave room for air to move between plants, which reduces leaf diseases.

Rotate your beds. Do not plant tomatoes where tomatoes, potatoes, peppers or eggplant grew in the last three years, as they share soil-borne diseases such as early blight, fusarium and verticillium wilt.

Tomatoes grow best when days are about 70°F to 75°F. Heat stress starts when days reach the high 80s °F and nights stay above about 70°F; then large-fruited varieties keep flowering but stop setting fruit. Nights below about 55°F also cause flowers to drop. Cherry and grape types set fruit in heat far better.

• North Florida and the Gulf South: set out transplants from about mid-March after the last frost, and again in July or August for a fall crop.
• Central Florida: plant in January and February and again in August and September, skipping the hot, humid, disease-prone summer.
• South Florida: plant from August through February; the cool, dry season is the main tomato season.
• Texas and the Desert Southwest: plant early, in late February or March, so fruit sets before summer heat, and again in July or August for fall.
• California: plant from March into early summer; coastal gardens can keep planting later.
• Mid-South, Mid-Atlantic and Southern Plains: plant from late April or May into early summer, with a midsummer planting for fall where the season allows.
• Northeast, Midwest, Northern Plains, Mountain West and the Pacific Northwest: plant in late May or June after frost; black plastic mulch and row covers help early plantings, and early varieties suit short seasons.
• Hawaii: any month, with cooler months best in the lowlands. Alaska: grow in a greenhouse or high tunnel, planted in June.

Choosing a variety

• Indeterminate (vining) varieties, such as Better Boy, Cherokee Purple and most cherry tomatoes, keep growing and fruiting until frost and need tall cages or stakes.
• Determinate (bush) varieties, such as Celebrity and most paste tomatoes like Roma, grow 3 to 4 feet tall and ripen most of their crop over a few weeks, which suits canning and small spaces.
• Cherry and grape tomatoes, such as Sweet 100, are the most forgiving and set fruit in summer heat. In South Florida, the tiny Everglades tomato thrives through heat and humidity.
• In hot areas, choose heat-setting varieties such as Heat Wave II.
• Look for disease-resistance codes on the label: V and F for verticillium and fusarium wilt, N for nematodes, and TYLCV resistance in Florida and the Gulf, where whiteflies spread tomato yellow leaf curl virus.

How to plant

1. Start seed indoors 6 to 8 weeks before your transplant date, or buy sturdy, dark green transplants without flowers or fruit.
2. Harden off transplants outdoors for a week before planting.
3. Work compost and a balanced fertilizer into the bed. Put cages or stakes in place at planting so you do not damage roots later.
4. Remove the lowest leaves and plant deeper than the transplant grew in its pot; roots form along the buried stem. Leggy plants can be laid sideways in a trench with just the top showing.
5. Water in with a starter fertilizer, then mulch with straw, shredded leaves or black plastic once the soil is warm.
6. Tie stems loosely to stakes or guide them inside the cage as they grow.

Watering and feeding

Water deeply and regularly at the base, not over the leaves, keeping soil moisture even. Long soaks that wet the soil 6 to 8 inches down are better than frequent sprinkles; about 1 to 2 inches a week in summer is typical, and containers may need water daily. Uneven watering is the main cause of blossom end rot and split fruit, and mulch helps keep moisture steady.

Feed with a balanced fertilizer at planting. Illinois Extension suggests side-dressing with nitrogen when the first fruits are golf-ball size, then twice more at three-week intervals. Too much nitrogen early gives big, leafy plants with few fruit.

Pruning and care through the year

• Staked indeterminate tomatoes are usually pruned to one or two main stems by pinching out the side shoots (suckers) between the main stem and leaf branches. Caged plants and determinate types need little or no pruning; heavy pruning can increase sunscald and blossom end rot.
• Remove yellowing lower leaves that touch the soil to slow early blight.
• In very hot weather, light shade cloth over the plants in the afternoon can help fruit set and reduce sunscald.
• Scout every few days for hornworms and other pests; catching problems early is the best control.

Harvesting

Tomatoes taste best when they ripen on healthy vines and are firm and fully colored. In hot summer weather, or where birds, squirrels or splitting are a problem, pick every day or two once color starts to show and finish ripening them indoors at 70°F to 75°F.

Before a killing freeze, pick all mature green fruit and ripen it indoors. Store ripe tomatoes at room temperature, not in the fridge, for the best flavor.

Growing in pots

Use a container of at least 5 gallons, about 20 inches wide, per plant, filled with a quality potting mix, with a cage or stake. Determinate, dwarf and cherry varieties suit pots best. Water daily in hot weather and feed regularly, as pots dry out and leach nutrients quickly. In Florida, lightweight pots can be moved to shelter when a late frost threatens.

Saving seed

Open-pollinated and heirloom varieties come true from seed. Scoop the seeds from a fully ripe fruit, let them ferment in a little water for two or three days, rinse, dry on a plate and store cool and dry. Hybrid (F1) seed will not grow true to the parent.