Growing Tomatoes: Complete Guide From Seed to Harvest
Tomatoes are the most popular home garden crop, and for good reason: a single well-grown plant can produce 10 to 25 pounds of fruit over a season, far exceeding the quality and flavor of grocery store tomatoes. But tomatoes are also among the most challenging crops to grow well. Disease, pests, watering issues, and nutrient problems frustrate many growers. This guide covers the key decisions and practices that separate mediocre tomato plants from productive, healthy ones.
Choosing Tomato Varieties
Determinate varieties grow to a set size, produce fruit over a concentrated 2 to 3 week window, and stop growing. They are ideal for canning, small spaces, and containers. Popular determinates include Roma, Celebrity, and Patio Princess. Indeterminate varieties grow continuously, producing fruit over the entire season until frost. They yield more total fruit but require staking and pruning. Popular indeterminates include Cherokee Purple, Brandywine, Sun Gold, and Better Boy.
Disease resistance is printed on variety tags as letters: V (verticillium wilt), F (fusarium wilt), N (nematodes), T (tobacco mosaic virus), A (alternaria). If your area has a history of specific diseases, choose resistant varieties. For most home gardens, selecting at least one disease-resistant hybrid alongside your heirloom favorites provides insurance against total crop loss.
- Determinate: set size, concentrated harvest, good for containers/canning
- Indeterminate: continuous growth and harvest, needs staking and pruning
- Cherry types: most productive and disease-resistant, great for beginners
- Heirlooms: best flavor, less disease resistance
- Hybrids: more disease resistance, consistent production
- Check disease resistance codes: V, F, N, T, A on variety tags
Planting for Success
Tomatoes need full sun: 8 or more hours of direct sunlight daily. Less than 6 hours significantly reduces fruit production. Plant after all danger of frost has passed and soil temperature is consistently above 60 degrees Fahrenheit. In most zones, this is 2 weeks after the last frost date.
Plant tomatoes deep: bury the stem up to the lowest set of leaves. Tomatoes form roots along the buried stem, creating a stronger root system. Dig a hole 6 to 8 inches deeper than the root ball and remove the lower leaves before planting. This technique is unique to tomatoes and significantly improves plant vigor, especially for leggy transplants.
Staking, Caging, and Pruning
Indeterminate tomatoes must be supported to keep fruit off the ground and improve air circulation. Cages (the round wire type sold at garden centers) work for determinate varieties but are usually too small for indeterminates. Stake-and-weave systems (driving a stake every 2 plants and weaving twine along the row) are more effective. Heavy-duty cages made from concrete reinforcing wire ($5 to $10 each, 5 feet tall) provide the best support.
Pruning indeterminate tomatoes increases fruit size and reduces disease. Remove suckers (shoots growing from the joint between the main stem and a branch) below the first flower cluster. Above the first cluster, you can let some suckers grow to form additional fruiting stems, but removing most keeps the plant open for air circulation. Determinate tomatoes should not be pruned because removing growth removes potential fruit.
Watering and Fertilizing
Tomatoes need consistent moisture: 1 to 2 inches of water per week, applied deeply rather than frequently. Inconsistent watering (dry spells followed by heavy watering) causes blossom end rot and fruit cracking. Drip irrigation or soaker hoses deliver water to the root zone without wetting the foliage, which reduces disease.
Fertilize at planting with a balanced fertilizer. Once fruit begins to set, switch to a lower-nitrogen, higher-phosphorus and potassium fertilizer (like 5-10-10 or a tomato-specific formula). Excessive nitrogen produces lush foliage but few tomatoes. A side-dressing of compost or granular fertilizer every 3 to 4 weeks through the season maintains steady nutrition.
Managing Common Tomato Problems
Early blight shows as concentric brown rings on lower leaves, progressing upward. Remove affected leaves promptly, improve air circulation, and apply copper fungicide preventively. Late blight is more destructive, appearing as water-soaked gray-green lesions that spread rapidly in cool, wet weather. There is no cure; remove and destroy affected plants immediately.
Blossom end rot (black, leathery spot on the bottom of fruit) is caused by calcium deficiency related to inconsistent watering, not a disease. Maintain even soil moisture. Cracking is caused by sudden water uptake after dry conditions. Catfacing (distorted, scarred fruit) results from cool temperatures during flowering. Most cosmetic problems do not affect flavor or safety.
Frequently Asked Questions
How many tomato plants do I need?
For fresh eating, 2 to 4 plants per person is sufficient. For canning and preserving, plan 5 to 8 plants per person. A single indeterminate plant produces 10 to 25 pounds of fruit over a season. Cherry tomato plants produce even more by count.
Why are my tomato leaves turning yellow?
Lower leaf yellowing is normal as the plant ages and redirects energy to fruit. Widespread yellowing may indicate nitrogen deficiency (fertilize), overwatering (reduce frequency), or early blight (remove affected leaves). Check the pattern: if only lower leaves are affected and the plant is otherwise healthy, it is usually not a serious concern.
Should I prune tomato suckers?
For indeterminate varieties, yes. Remove suckers below the first flower cluster and optionally above it to maintain an open, well-supported plant. For determinate varieties, do not prune because each branch produces fruit. Cherry tomato plants can be left unpruned if you want maximum production and have adequate support.
What causes blossom end rot?
Inconsistent watering causes the plant to be unable to transport enough calcium to developing fruit. The solution is maintaining even soil moisture through regular watering and mulching, not adding calcium to the soil (most soils have adequate calcium). Once affected fruit shows symptoms, it will not recover, but subsequent fruit can be normal if watering is corrected.
When should I harvest tomatoes?
Harvest when fruit is fully colored and gives slightly when gently squeezed. Tomatoes ripen from the inside out, so even slightly firm fruit will continue to ripen on the counter. In late season before frost, pick green tomatoes and ripen them indoors in a single layer at room temperature. They will not be as flavorful as vine-ripened but are much better than letting them freeze.