Tomatoes are the crop most home gardeners start with, and for good reason: the flavor gap between homegrown and store-bought is enormous, and they respond visibly and quickly to good care. They do ask for a few things you have to get right, particularly sun, timing, and water consistency. Get those three right and the rest follows.
When to plant tomatoes
Tomatoes are frost-tender and cold-sensitive. They will not tolerate a freeze, and they struggle when nighttime temperatures fall below 50 degrees F, even without frost. The goal is to transplant into the garden after your last frost date has passed and nights have warmed.
Most gardeners transplant tomatoes outdoors 2 weeks after their average last frost date, once soil temperatures have reached at least 60 degrees F. If you are starting from seed indoors, begin 6 to 8 weeks before your last frost date.
If you are starting from seed, read our guide to how to start seeds indoors and how to harden off seedlings before moving transplants outside.
Where to plant: sun and soil
Sun: Tomatoes need at least 8 hours of direct sun daily, and they perform best with closer to 10 hours. They will grow in 6 hours but produce less and become more disease-prone. Site your tomatoes in your sunniest unshaded spot.
Soil: Tomatoes want loose, well-draining, fertile soil with a pH between 6.0 and 6.8. Before planting, work 2 to 3 inches of compost into the top 12 inches of soil. Good organic matter helps with moisture retention, which directly reduces the risk of blossom end rot.
Raised beds are an excellent option for tomatoes because you control the soil quality entirely. Our guide to raised bed gardening for beginners covers how to build a soil mix that performs well all season.
Spacing and support
Tomatoes come in two growth habits, and your spacing depends on which type you grow.
Indeterminate vs. determinate
Indeterminate varieties
Keep growing and producing until frost. They get tall (often 5 to 8 feet) and must be staked or caged. Space them 24 to 36 inches apart, with rows 4 to 5 feet apart. Beefsteak, Cherokee Purple, and most heirlooms are indeterminate.
Determinate (bush) varieties
Grow to a fixed size and ripen most of their fruit in a short window. Space them 18 to 24 inches apart. Better Boy, Celebrity, and Roma are common determinates.
Support from day one: Drive stakes or set cages at planting time, not later when disturbing roots becomes a problem. A single sturdy 6-foot stake works for staking; a heavy-gauge wire cage at least 18 inches wide suits most indeterminates.
Bury the stem deeply: Unlike most transplants, tomatoes root along their buried stems. Plant so that only the top two sets of leaves show above soil. This builds a stronger root system and produces a sturdier plant.
Watering and feeding
Consistent moisture is the single most important watering rule for tomatoes. Uneven watering, alternating drought and flood, directly causes blossom end rot and growth cracks. Aim for 1 to 2 inches of water per week, delivered slowly so it soaks deep rather than running off.
A soaker hose running at the base keeps water off the foliage (wet leaves spread early blight, late blight, and septoria leaf spot) and delivers water directly where roots can use it.
Feeding: At planting, work a slow-release tomato fertilizer into the planting hole. Once fruit sets, side-dress every 3 to 4 weeks. Avoid high-nitrogen feeds after fruit set; they push leafy growth at the expense of fruit and can worsen calcium transport, contributing to blossom end rot.
Common problems to watch for
Tomatoes attract a reliable cast of problems. Knowing them makes them manageable.
Diseases:
- Early blight: Dark concentric spots on lower leaves mid-season. Mulch and avoid overhead watering.
- Late blight: Water-soaked patches that turn brown-black fast in cool, wet weather. Remove affected tissue immediately.
- Septoria leaf spot: Small circular spots with dark borders on lower leaves. Strip affected leaves and improve airflow.
Fruit disorders:
- Blossom end rot: Dark, leathery patches on the bottom of the fruit. Caused by inconsistent watering and poor calcium transport, not a disease.
- Sunscald: White or tan papery patches on fruit facing the sun, usually after leaves are removed. Leave some foliage for shade.
- Growth cracks: Radial or concentric splits near the stem. Caused by rapid water uptake after dry spells.
- Catfacing: Scarring and deformity at the blossom end. Usually tied to cool temperatures during flower set.
Pests:
- Tomato hornworm: Large green caterpillars that defoliate plants quickly. Scout in early morning; handpick when found. According to Utah State University Extension, monitoring from early July through mid-summer is the key window.
See our mulching guide for how to apply mulch effectively around vegetable plants.
Harvesting tomatoes
Most varieties are ready to harvest 65 to 85 days after transplanting. The signs are more reliable than the calendar:
- The fruit has reached its expected size for the variety.
- Color is fully developed (red, orange, yellow, or whatever the variety's ripe color is) all the way to the shoulder.
- The fruit gives slightly to gentle pressure.
- The stem separates cleanly with a gentle twist.
Do not refrigerate freshly harvested tomatoes. Cold damages the texture and kills the flavor compounds that make homegrown tomatoes worth growing. Keep them at room temperature out of direct sun and use within a few days.
Growing in containers
Tomatoes grow well in large containers if you choose compact or patio varieties. Use a pot at least 15 to 20 gallons for indeterminate types, or 5 gallons for true dwarf varieties. Containers dry out much faster than beds, so check soil moisture daily and expect to water more frequently.
Our container gardening guide covers soil, container sizing, and watering for vegetables.
For related reading, see how peppers follow a similar warmth-and-sun profile, and how companion planting can pair basil and marigolds with tomatoes for pest management.
When should I plant tomatoes outdoors?
Transplant tomatoes after your last frost date once nighttime temperatures stay consistently above 50 degrees F and soil temperatures have reached at least 60 degrees F. Starting from seed indoors? Sow 6 to 8 weeks before your last frost. Use our frost dates tool and planting calendar to find your exact window by ZIP code.
How far apart do tomatoes need to be spaced?
Indeterminate (vining) varieties need 24 to 36 inches between plants, with rows spaced 4 to 5 feet apart. Determinate (bush) varieties can be spaced 18 to 24 inches apart. Crowding reduces airflow and increases disease pressure, so err on the wider side. Use our spacing calculator to map out your bed.
How much water do tomato plants need?
Tomatoes need about 1 to 2 inches of water per week, delivered consistently. Uneven watering causes blossom end rot and cracking. Water deeply at the base rather than from overhead, and mulch around plants to retain moisture and reduce the wet-dry swings that cause problems.
Why does my tomato have dark spots on the bottom of the fruit?
Dark, sunken, leathery spots on the blossom end of the fruit are blossom end rot. It is caused by inconsistent watering and poor calcium transport, not a disease. Water evenly, mulch to retain moisture, and avoid heavy nitrogen fertilizer. The next flush of fruit is usually fine once watering is corrected.
How do I know when tomatoes are ready to pick?
A ripe tomato has reached its full mature color all the way to the shoulder, gives slightly to gentle pressure, and separates cleanly with a gentle twist. Most varieties ripen 65 to 85 days after transplanting. Do not refrigerate harvested tomatoes; keep them at room temperature and use within a few days for best flavor.