Early blight generally attacks older plants, but it can also occur on seedlings.
Stressed plants or plants in poor health are especially susceptible.
What Is Tomato Blight?
The Spruce / Adrienne Legault
However, more than one bang out of blight can attack tomatoes at the same time.
There are three types of tomato blight because of different fungi that all present somewhat similarly.
Types of Tomato Blight
What Causes Early Blight?
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The early blight fungus can come from many sources.
It can be in the soil, or it can already be on seeds or seedlings you purchase.
These spots can spread and clump together, destroying leaf tissue.
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Early blight is sometimes confused withSeptoria leaf spot.
On Older Plants:Dark spots with concentric rings develop on older leaves first.
The surrounding leaf area may turn yellow.
Affected leaves may die prematurely, exposing the fruits to sun-scald.
Dark lesions on the stems start small and are slightly sunken.
Spots that form near ground level can cause some girdling of the stem or collar rot.
Plants may survive, but they will not thrive or produce many tomatoes.
Both green and ripe tomatoes can be affected.
On Seedlings:Affected seedlings will have dark spots on their leaves and stems.
They may even develop the disease on their cotyledon leaves.
Stems often wind up girdled.
These measures, however, can help you keep it under control and prevent the issue.
What Causes Late Blight?
The pathogen thrives in cool, wet weather, and affects the above-ground portions of the plant.
Spores will form on the diseased tissue.
Spots will also appear on both sides of the leaves.
As blight continues to take hold, leaves will become brown, shrivel, and die.
You will notice rotten fruit has greasy brown spots that will eventually look and feel like leather.
Remove any compromised areas of your plants immediately.
It is much less common for tomatoes to survive with late blight.
Yes, tomato blight can be spread to plants such as potatoes and other nightshade vegetables.
Early Blight and Late Blight of Potatoes.University of Connecticut.
College of Agriculture, Health, and Natural Resources.
Tomato Disorders.University of Wisconsin-Madison.
Late Blight of Tomatoes and Potatoes.
University of Minnesota Extension.
Early Blight of Tomato.University of Minnesota Extension Office.
Ivors, Kelly.Late Blight of Tomato.
Late blight of tomato and potato.
University of Minnesota Extension.
Late blight Management for Fall, Winter and Spring.University of Massachusetts Extension.
Are tomatoes and potatoes with late blight safe for eating and canning?Michigan State University.
Soil Solarization for Gardens and Landscapes.Agriculture and Natural Resources, University of California.
