Start with seeds or seedlings, depending on your timeline and space
You can grow tomatoes from seed indoors six to eight weeks before your last spring frost, or buy seedlings from a garden center and plant them directly outside after the frost date has passed. Seeds take longer but cost less and give you more variety to choose from. Seedlings are faster—you can have plants in the ground within weeks—but your choices are limited to what local nurseries stock.
If you start from seed, use seed-starting mix (not garden soil) in small containers with drainage holes. Keep the soil moist but not waterlogged, and place the containers in a warm spot—a sunny windowsill or under grow lights works well. Once seedlings develop their first true leaves (the second set that appears), thin them so each plant has room to grow without crowding.
Whether you use seeds or seedlings, harden them off before planting outside. This means gradually exposing them to outdoor conditions over seven to ten days—start with an hour in shade, then increase sun and time each day. This prevents shock when they go into the ground.
Key Takeaways
- Tomatoes need at least six to eight hours of direct sunlight daily and soil that drains well; raised beds or containers work if your yard is shaded or has poor soil.
- Plant seedlings deeper than they were growing in their containers—bury the stem up to the first true leaves to encourage a stronger root system.
- Water at the soil level early in the morning, aiming for one to two inches per week; wet leaves invite disease.
- Determinate varieties (bush types) need minimal pruning, while indeterminate varieties (vining types) need regular removal of suckers to focus energy on fruit.
- Harvest tomatoes when they reach full color; they will continue to ripen off the vine if picked at the breaker stage (when color just begins to show).
Choose a location with full sun and prepare the soil
Tomatoes need at least six to eight hours of direct sunlight each day to produce fruit and develop flavor. If your yard is shaded, use containers on a sunny patio or deck instead. Full sun also helps prevent fungal diseases that thrive in damp, shaded conditions.
Prepare the soil by mixing in compost or aged manure before planting. Tomatoes are heavy feeders and need rich, well-draining soil with a pH between 6.0 and 6.8. If your soil is clay-heavy or compacted, build a raised bed or use containers filled with quality potting mix. Poor drainage causes root rot and fungal problems that are hard to fix once they start.
Test your soil if you can—many county extension offices offer inexpensive soil tests that tell you what nutrients are present and what you need to add. This saves money on fertilizer and prevents over-feeding, which produces leafy plants with few tomatoes.
Plant seedlings deep and space them correctly
When transplanting seedlings outdoors, bury the stem deeper than it was growing in its pot. Bury it up to the first set of true leaves—tomatoes will develop roots all along the buried stem, creating a stronger root system. This is one of the most important steps for healthy plants.
Space plants 24 to 36 inches apart, depending on the variety. Determinate (bush) types can be closer; indeterminate (vining) types need more room for air circulation. Crowded plants trap moisture and invite disease. If you are planting in containers, use a pot at least five gallons for determinate varieties and ten gallons for indeterminate ones.
Plant in late spring after the last frost date in your area. Tomatoes are frost-sensitive and will die if exposed to temperatures below 50°F. Check your local frost date through your county extension office or a gardening website specific to your region.
Water consistently and at the right time of day
Tomatoes need one to two inches of water per week, delivered steadily rather than in feast-or-famine cycles. Inconsistent watering causes blossom-end rot (dark spots on the bottom of fruit) and fruit cracking. Water deeply at the soil level in the early morning, before the heat of the day.
Water the soil, not the leaves. Wet foliage invites fungal diseases like early blight and powdery mildew, which spread quickly in humid conditions. Drip irrigation or soaker hoses deliver water directly to the roots and are more efficient than overhead sprinklers. If you water by hand, aim the hose at the base of each plant.
In hot weather, you may need to water every two to three days. In cooler weather or after rain, check the soil before watering—stick your finger two inches into the soil, and water only if it feels dry at that depth. Overwatering is as harmful as underwatering.
Support vining plants and prune as needed
Determinate (bush) tomatoes grow to a fixed size and need little support beyond a short cage or stake. Indeterminate (vining) tomatoes grow continuously throughout the season and need sturdy support—a tall cage, stake, or trellis. Install support at planting time to avoid damaging roots later.
Indeterminate varieties also benefit from pruning. Remove suckers—the shoots that grow between the main stem and branches—to direct energy into fruit production rather than excessive foliage. Pinch off suckers when they are small, before they become woody. Stop pruning in late summer so the plant can focus on ripening existing fruit before frost.
Determinate varieties produce most of their fruit at once and do not need sucker removal. Pruning them reduces yield, so leave them alone except to remove diseased or damaged branches.
Fertilize regularly but do not overdo it
If you mixed compost into the soil at planting, your tomatoes have nutrients to start with. Once flowering begins, feed every two to three weeks with a balanced fertilizer or one slightly higher in phosphorus and potassium (the second and third numbers on the package). Too much nitrogen produces leafy plants with few flowers and little fruit.
Use a liquid fertilizer, granular slow-release fertilizer, or fish emulsion—all work well. Follow the package directions for rates and frequency. If leaves turn yellow, it may signal nitrogen deficiency, but it can also mean overwatering or poor drainage, so check soil moisture before adding more fertilizer.
Calcium deficiency causes blossom-end rot. If this appears, add crushed eggshells or a calcium supplement to the soil, and maintain consistent watering to help the plant absorb calcium.
Identify and manage common pests and diseases
Hornworms and whiteflies are the most common pests. Hornworms are large green caterpillars that eat leaves and fruit; pick them off by hand or use neem oil spray. Whiteflies cluster on the undersides of leaves and weaken the plant; spray with insecticidal soap or neem oil, hitting the undersides of leaves.
Early blight appears as brown spots with concentric rings on lower leaves and spreads upward. Remove affected leaves and improve air circulation by pruning. Powdery mildew looks like a white coating on leaves; spray with sulfur or a fungicide labeled for tomatoes. Both diseases thrive in wet conditions, so water at soil level and avoid wetting leaves.
Septoria leaf spot causes small circular spots with dark borders and gray centers. Remove affected leaves and dispose of them in the trash, not the compost pile. Fungal spores overwinter in plant debris, so clean up fallen leaves and old plants at the end of the season.
Harvest tomatoes at the right stage
Pick tomatoes when they reach full color—red, pink, yellow, or whatever color your variety is supposed to be. Ripe tomatoes come off the vine easily with a gentle twist. If you pick them slightly early at the breaker stage (when color just begins to show), they will continue to ripen indoors and you avoid losing them to birds or splitting from rain.
Tomatoes ripen faster in warm conditions. Store them at room temperature, not in the refrigerator—cold temperatures break down flavor compounds and make the texture mealy. Once ripe, use them within a few days for best flavor.
At the end of the season, when frost is forecast, pick all remaining fruit—even green ones. Green tomatoes will ripen indoors in a paper bag or on a windowsill over one to two weeks. This salvages fruit that would otherwise be lost to frost.
Frequently Asked Questions
Can I grow tomatoes in containers on a balcony?
Yes, as long as the balcony gets at least six to eight hours of direct sun. Use containers at least five gallons for determinate varieties and ten gallons for indeterminate ones. Containers dry out faster than garden soil, so check moisture daily and water more often, especially in hot weather.
Why are my tomato flowers dropping without making fruit?
Flowers drop when temperatures fall below 55°F at night or exceed 90°F during the day, when watering is inconsistent, or when nitrogen is too high. Check your watering schedule and soil fertility. Early-season flower drop is normal; the plant will produce more flowers as conditions improve.
What is the difference between determinate and indeterminate tomatoes?
Determinate varieties grow to a fixed size, produce most fruit at once, and are good for canning or sauces. Indeterminate varieties grow continuously, produce fruit throughout the season, and are better for fresh eating. Check the seed packet or plant label to know which type you have.
Can I save seeds from my tomatoes for next year?
Yes, but only from heirloom or open-pollinated varieties. Hybrid tomatoes will not produce seeds that grow into plants identical to the parent. Scoop seeds into a jar with a little water, let them ferment for two to three days, rinse them, and dry them completely on a plate before storing in a cool, dry place.
When should I stop watering my tomato plants?
Continue watering until frost kills the plants. Stopping water early stresses the plant and can cause fruit to crack or split. Once frost is forecast, pick all remaining fruit and pull up the plants to clear the garden for fall crops.