Start with seeds or seedlings, then move to soil and sunlight
Growing tomatoes begins with a choice: start 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 frost danger passes. Seeds take longer but cost less and give you more variety to choose from. Seedlings are faster and require less equipment—just a sunny windowsill or grow light if you start from seed.
Tomatoes need at least six to eight hours of direct sunlight daily to produce fruit. They also need soil that drains well and holds some moisture without becoming waterlogged. Whether you plant in a garden bed, a raised box, or a large container (at least five gallons), the soil should be loose enough for roots to push through easily.
Key Takeaways
- Tomato seeds started indoors need six to eight weeks before your last frost date, while store-bought seedlings go straight into the ground after frost danger ends.
- Plants need six to eight hours of direct sun daily and soil that drains well but retains moisture—add compost or aged manure to improve garden soil.
- Space plants two to three feet apart, bury the stem deeper than it grew in its pot, and water at the base rather than on leaves to prevent disease.
- Determinate varieties (bush types) produce all their fruit at once; indeterminate varieties (vining types) produce fruit throughout the season and need staking or caging.
- Pinch off suckers on indeterminate plants, remove lower leaves as the plant grows, and harvest fruit when it reaches full color but is still slightly firm.
Planting depth and spacing matter more than most gardeners realize
When you move a seedling from its pot to the ground, bury it deeper than it was growing in the container. Tomatoes can develop roots all along the buried stem, which creates a stronger root system. Bury the seedling up to its first true leaves—the lowest set of leaves that look like actual tomato leaves, not the smooth oval seed leaves that appeared first.
Space plants two to three feet apart, depending on the variety. Determinate tomatoes (bush types that stay compact) can be closer together. Indeterminate tomatoes (vining types that grow tall all season) need more room for air to circulate around the leaves. Poor air circulation traps moisture and invites fungal disease.
If you are planting in a container, use a pot at least five gallons in size and fill it with potting soil, not garden soil. Garden soil compacts in containers and prevents drainage. Add a handful of compost to the bottom of the pot before planting to provide nutrients as the plant grows.
Water at the base, not the leaves, to prevent disease
Tomatoes need consistent moisture—not soggy, not bone-dry. Water deeply at the base of the plant early in the morning, aiming the water at the soil rather than splashing the leaves. Wet leaves invite early blight and powdery mildew, two common fungal diseases that spread quickly in humid conditions.
Check the soil with your finger before watering. If the top inch feels dry, water. If it still feels moist, wait another day. In hot weather, this might mean watering every day or every other day. In cooler weather or after rain, you may water only once or twice a week.
Mulch around the base of the plant with two to three inches of straw, wood chips, or shredded leaves. Mulch keeps soil moisture consistent, prevents soil from splashing onto leaves during rain, and keeps the soil cooler during heat waves.
Support indeterminate plants with stakes or cages early
Determinate tomatoes (bush varieties) usually need little or no support—they grow to a set height and stop. Indeterminate tomatoes (vining varieties) grow taller throughout the season and need support to keep fruit off the ground and improve air circulation.
Install a stake or cage when you plant, not later. Waiting until the plant is tall risks damaging roots when you push a stake into the soil. A wooden stake four to six feet tall works well for indeterminate varieties; tie the main stem loosely to the stake with soft twine or cloth strips as it grows. A sturdy cage (not the flimsy wire ones sold in most stores) also works if it is at least five feet tall.
As indeterminate plants grow, pinch off suckers—the small shoots that grow between the main stem and branches. Removing suckers directs energy into fruit production rather than extra foliage. Leave the suckers on determinate plants; they produce fruit.
Feed the plant as fruit begins to form
Tomatoes are heavy feeders, especially once flowering starts. If you mixed compost into the soil at planting time, the plant has some nutrients to start with. Once flowers appear and fruit begins to set, feed every two to three weeks with a balanced fertilizer (equal parts nitrogen, phosphorus, and potassium) or a fertilizer higher in phosphorus and potassium, which promote fruiting.
Follow the package directions for the amount and frequency. Too much nitrogen produces lots of leaves but few tomatoes. Too little nutrition results in small fruit or fruit that cracks as it grows.
Remove the lowest leaves on indeterminate plants once the plant is three to four feet tall. These lower leaves are most likely to develop disease, and removing them improves air circulation. Stop removing leaves once fruit begins to ripen; the leaves protect fruit from sunscald.
Harvest when fruit reaches full color but is still slightly firm
Tomatoes ripen from the inside out. A ripe tomato should feel slightly soft when you squeeze it gently—not hard, not mushy. The color should be fully developed: red for most varieties, orange or yellow for those types, pink for pink varieties. If you wait until the tomato is very soft, it may split or crack.
Twist the tomato gently or use a small knife to cut the stem. If a tomato is nearly ripe but the season is ending (frost is coming), pick it at the breaker stage—when the first blush of color appears—and ripen it indoors on a windowsill. Tomatoes picked at this stage will ripen fully in a few days.
Determinate varieties produce most of their fruit within a short window, often two to three weeks. Indeterminate varieties produce fruit continuously until frost kills the plant, usually producing for two to three months or longer in warm climates.
Common problems and how to prevent them
Blossom end rot appears as a dark, sunken spot on the bottom of the fruit. It is caused by inconsistent watering and calcium deficiency in the fruit. Prevent it by watering consistently and mulching to keep soil moisture even. Once it appears on a fruit, that fruit cannot be saved, but consistent watering prevents it on new fruit.
Cracking or splitting happens when the plant receives heavy rain or watering after a dry period. The fruit absorbs water too quickly and the skin splits. Prevent this by watering consistently rather than letting the soil dry out and then soaking it. Mulch helps by keeping moisture even.
Early blight shows as brown spots with concentric rings on lower leaves. It spreads upward and can defoliate the plant. Prevent it by removing lower leaves, watering at the base only, and improving air circulation. Remove affected leaves as soon as you see them and dispose of them in the trash, not the compost pile.
Sunscald appears as pale, papery patches on fruit exposed to intense afternoon sun. It is more common in very hot climates. Prevent it by keeping enough foliage on the plant to shade the fruit, especially on the south and west sides.
Frequently Asked Questions
Can I grow tomatoes in a pot on a patio or balcony?
Yes. Use a container at least five gallons in size, fill it with potting soil, and place it where it gets six to eight hours of direct sun daily. Water more often than garden tomatoes because containers dry out faster. Determinate varieties work better in containers than indeterminate ones, though dwarf indeterminate varieties are available.
What is the difference between determinate and indeterminate tomatoes?
Determinate tomatoes are bush types that grow to a set height (usually two to three feet), produce most fruit at once, and stop growing. Indeterminate tomatoes are vining types that grow taller all season, produce fruit continuously until frost, and need staking or caging. Determinate varieties are good for canning; indeterminate varieties produce fresh tomatoes over a longer period.
Why are my tomato flowers falling off without making fruit?
Flowers drop when temperatures are too hot (above 90 degrees at night), too cold (below 55 degrees), or when the plant is stressed by inconsistent watering or too much nitrogen fertilizer. may support consistent watering, avoid over-fertilizing with nitrogen, and be patient—once temperatures moderate, new flowers will form and set fruit.
How do I know when to pick a tomato?
Pick when the tomato is fully colored and yields slightly to gentle pressure. It should not be hard or mushy. If frost is coming and tomatoes are still green or just starting to color, pick them at the breaker stage (first color showing) and ripen them indoors on a windowsill.
Do I need to prune tomato plants?
Pruning is optional for determinate varieties but helpful for indeterminate ones. Pinch off suckers on indeterminate plants to direct energy into fruit production. Remove lower leaves as the plant grows to improve air circulation and prevent disease. Determinate plants produce fruit on suckers, so leave them alone.