Why Do My Tomato Leaves Have Spots?
Tomato leaf spots are usually caused by fungal or bacterial diseases, though nutrient stress, insect feeding, and spray injury can also mark foliage. Identify the spot pattern first, then remove affected leaves, keep foliage dry, and improve airflow to slow further spread.
Early blight commonly starts on older, lower leaves as brown spots with concentric rings, often surrounded by yellow tissue. Septoria leaf spot makes many small, round gray or tan spots with darker borders, also beginning low on the plant. Both diseases survive in soil and plant debris, and rain or overhead watering splashes spores onto leaves.
Bacterial spot and bacterial speck can produce small dark, greasy-looking spots that may have yellow halos. They spread readily when plants are handled while wet. Do not prune, tie, or harvest wet tomato plants, and disinfect tools after working on plants with suspicious spotting.
Remove the worst affected lower leaves and any leaves resting on the soil, placing them in the trash rather than a home compost pile. Stake, cage, or trellis plants so foliage dries quickly, and space plants according to the mature width on the label, often 24 to 36 inches apart. Water at the soil line early in the day instead of wetting leaves.
Mulch with clean straw, untreated leaves, or another organic mulch after the soil has warmed. A 2- to 3-inch layer reduces soil splash, conserves moisture, and helps keep lower foliage cleaner. Avoid crowding mulch directly against stems, and keep watering consistent because stressed plants are less able to replace damaged foliage.
Yellow patches without distinct, expanding spots can point to uneven watering, compacted roots, or a nutrient issue rather than an infectious leaf disease. Check whether the oldest leaves are yellowing evenly, whether soil stays soggy, and whether the plant is growing normally. A soil test through a local Cooperative Extension office is the best way to confirm nutrient needs before adding fertilizer.
Rotate tomatoes and related crops, including peppers, potatoes, and eggplants, away from the same bed for at least two to three years when leaf diseases have been severe. At season's end, remove vines and fallen leaves, clean cages and stakes, and choose disease-resistant varieties when available. If disease continues to advance despite sanitation, use only products labeled for tomatoes and follow the label and local Cooperative Extension guidance.
Frequently asked questions
Should I remove spotted tomato leaves?
Remove heavily spotted lower leaves and leaves touching soil, but do not strip the plant bare. Leave enough healthy foliage to support fruit development and make clean cuts with sanitized pruners.
Can tomato leaf spot spread to other plants?
Many tomato leaf diseases spread among tomatoes and sometimes other closely related crops. Spores and bacteria are commonly moved by splashing water, wet hands, tools, and infected crop debris.
Will spotted leaves recover?
Existing spots do not heal. The goal is to protect new growth and keep enough healthy leaf area for the plant to finish the season.
General guidance for US home gardens. Conditions vary by region and season; check with your local Cooperative Extension office for site-specific advice. Page updated Aug 4, 2026.