Tomatoes are the headline act of the summer garden, and the growers who consistently get the best fruit are the ones who start early and stay on top of a few fundamentals. Begin seeds indoors six to eight weeks before your last frost — don't rush them outside until the soil has genuinely warmed to 60°F and nights are reliably above 50°F. Cold soil stalls growth and sets plants back further than if you'd just waited. Bury transplants deep, up to the first true leaves; tomatoes throw roots all along the buried stem and establish faster for it.
The two biggest splits in tomato growing are determinate versus indeterminate types. Determinate (bush) varieties set and ripen their entire crop within a few weeks — good for canning and preserving. Indeterminate types keep flowering and fruiting until frost, which means a longer harvest window but also a taller, unrulier plant that needs a strong stake or cage from the start. Don't wait until the plant is flopping over to support it. On indeterminate types, pinching the suckers — the shoots that emerge in the crotch between stem and branch — keeps energy focused on fruit rather than endless new foliage, though some gardeners let one sucker grow as a second leader.
Consistent, deep watering matters more than almost anything else. Irregular moisture is the cause of blossom-end rot and cracked fruit, two of the most common complaints. Water at the base, keep foliage dry, and mulch heavily to hold soil moisture and keep soil-borne diseases from splashing up onto lower leaves. Once fruit is setting, a low-nitrogen fertiliser encourages more fruit and less leaf. Tomatoes are prone to a long list of diseases — rotate them around the garden each year and remove any yellowing or spotted leaves promptly.
Growing tomatoes this year? Read the Tomato Growing Guide — the whole season from seed starting to sauce, timed to your frost dates.Early Blight
Dark brown spots with concentric rings on older lower leaves, surrounded by yellowing. Leaves drop, exposing fruit to sunscald.
Remove affected leaves, mulch to block soil splash, water at the base, and rotate crops. Apply copper or chlorothalonil fungicide if it spreads.
Septoria Leaf Spot
Small tan to brown spots with dark borders on leaves, often with tiny black specks at the center. Spots merge and lower leaves yellow and die.
Remove infected leaves and avoid overhead watering. Space plants for airflow and rotate planting location each year. Apply a copper-based fungicide if spread continues.
Fusarium wilt
Sudden wilting, brown streaks in stems, yellowing leaves. Affects sweet basil varieties most.
No cure. Remove and destroy plants. Do not replant in the same spot for 3+ years. Choose resistant varieties.
Verticillium Wilt
Lower leaves yellow and wilt, often on one side of the plant, with brown streaking in the stem and crown tissue when cut open. Plants are stunted and decline over the season.
Remove and destroy affected plants. Avoid planting in soil that has grown infected tomatoes, peppers, or other susceptible crops. Rotate beds and improve drainage; there is no cure once a plant is infected.
Blossom End Rot
Sunken, dark leathery patch on the bottom end of the fruit. Caused by calcium uptake disruption from uneven watering.
Maintain consistent soil moisture and mulch. Avoid overfertilizing with nitrogen. Test soil and amend calcium if deficient.
Mosaic virus
Yellowing, mottled, or distorted leaves. No cure — spread by aphids.
Remove and destroy infected plants. Control aphid populations to prevent spread. Do not propagate from infected tubers.
Tomato Hornworm
Manduca quinquemaculata →Large green caterpillars with a rear horn that strip leaves and chew into fruit. Dark droppings appear on foliage below.
Handpick and destroy caterpillars. Apply Bt (Bacillus thuringiensis) if heavy. Leave any with white wasp cocoons to host parasites.
Comfrey and the stinking jar
The single most useful plant in the garden is one you would never put in a vase, and the feed it makes smells appalling.
Five ways to fail a tomato
Almost everything that goes wrong with a tomato comes down to the same handful of small impatiences, and most of them can be undone.