#Early blight on tomato plants how to
#Early blight on tomato plants full

Photo by AmBNPHOTO/Shutterstock Is It Early Blight or Another Problem?Īs mentioned, several tomato diseases are commonly mistaken for each other. Infection happens near the stem, and the fruit may drop off.Įarly blight affecting the stem and leaves of a tomato plant.

Fruit can be infected and develops dark, leathery spots with raised ridges.

Stem infections are often oval in shape and also present in concentric rings.

They may fall off or remain attached to the plant as dried-out husks.

Eventually, infected leaves will turn brown completely and wither.

Leaf tissue surrounding the spots may turn yellow.

Early blight spots range from the size of a pencil eraser to almost as big as a dime.

Spots are brown and round and may develop concentric rings.

Small dark spots may appear on older leaves near the soil.

Watch for these signs when walking in your garden: The result is struggling or even dead plants, and a reduced harvest.Įarly blight begins on lower, older leaves in midsummer when temperatures warm. The Alternaria fungus also releases phytotoxins, toxic chemicals to the host plant-your tomato or potato. The spores can overwinter in the soil and in contaminated plant material.Įarly blight can cause cankers that girdle the plant. In other words, warm, humid summers with evening thunderstorms, like many of us experience in June, July, and August. High humidity levels, rain, and wind contribute to spreading Alternaria spores. Lower leaves commonly become infected when in contact with contaminated soil or when soil is splashed onto the leaves by rain or irrigation. If you are curious about the details of this fungus’ life cycle, check this summary from the National Center for Biotechnology Information.Īlternaria spores can be spread by wind, people and animals, and by contaminated tools. These spores are then ready to infect more areas of your plant or drift to an adjacent victim. Spores can be produced as quickly as 3-5 days after spots first appear. How Does Early Blight Spread?ĭuring wet or humid conditions, like warm days with significant rainfall or morning dew, the fungus that causes early blight can replicate rapidly. Two different species but the same genus. It is often confused with Septoria leaf spot, Verticillium and Fusarium wilts, and bacterial leaf spot.Įarly blight tomato infection is caused by the fungus Alternaria tomatophila and Alternaria solani.

This fungus first attacks the lower leaves of tomatoes, potatoes, peppers, etc., and moves up the plant. It also affects plants like peppers, potatoes, eggplants, and other members of the nightshade family. What Is Early Blight?Įarly blight is a fungal pathogen of tomatoes.

#Early blight on tomato plants how to

Here’s how to watch for signs of early blight and keep it in check. If left unchecked, it can destroy your tomato plants and severely hamper your harvest. Pruning off low leaves can slow the spread of the disease by reducing the number of spores present.Early blight of tomatoes is a common issue that many tomato gardeners face. Invisibly small spores are spread to new leaves by wind, rain and insects, where warm, damp conditions encourage them to germinate and grow. When watering tomatoes, avoid wetting the foliage. Use mulches to keep soil from splashing onto tomato leaves.

In early summer, clip off the first spotted leaves when you see them, and compost them in an active compost pile.

#Early blight on tomato plants full

Grow tomatoes at wide spacing in full sun, so their leaves dry promptly each morning and after rains. Try resistant varieties, which are new but very worthwhile. Most of the time early blight weakens plants but does not kill them. Tomatoes can tolerate losing some of their low leaves to early blight, but if persistent rain causes the disease to move more than halfway up the plants, they may be doomed. Early blight spreads fastest in humid weather when temperatures are between 80 and 85F (27-29C). Affected leaves gradually wither to brown and hang on the stems, while leaves higher up on the plant remain green and healthy. The irregularly-shaped spots have concentric rings around their edges, sometimes with a dark dot in the center. The most common cause of dark spots on tomato leaves, early blight begins on the oldest leaves closest to the ground. Worldwide, in temperate climates Description: