Juicy, perfectly sun-ripened tomatoes are among the easiest vegetables you’re free to grow in your garden.
With a little effort, your plants can stay healthy and productive all season long.
Diseases also can spread when leaves get wet, soavoid crowding your tomatoestoo close together.
Credit: Scott Little
This helpsair circulate betterand dries leaves faster.
Even when following all thesebest growing practices, some tomato plant diseases are likely to pop up.
But it’s almost inevitable that these plants will end up with a foliar disease or blemished fruit.
Credit: Denny Schrock
So here’s what to look for so you know what you are dealing with.
Anthracnose
This fungus is a small, circular, indented area on tomato fruits.
Eventually, rings surround the original spot.
Credit: Denny Schrock
Spores are spread by splashing water, and the fungus is most common during warm, wet weather.
The process continues until the entire plant is affected.
To help control these tomato plant diseases, plant tomatoes bred for disease resistance.
Credit: Peter Krumhardt
Early Blight (Alternaria)
Another tomato plant disease fungus,Alternaria, causes early blight.
Lower leaves show brown or black spots with dark edges, almost like a target.
Stem ends of fruits may be attacked, showing large, sunken black areas with concentric rings.
Credit: Scot Nelson
This fungus usually strikes after plants set fruit.
It looks almost likefrost damage on leaves, causing irregular green-black splotches.
Fruits may have large, irregular-shaped brown blotches that quickly become rotten.
Credit: Cameron Sadeghpour
This plant disease also affects potatoes and can be transferred from them.
Mosaic Virus
Mosaic virus attacks many kinds of plants and is a common tomato plant disease.
While mosaic virus doesn’t kill the plant, it diminishes the number and quality of fruits.
Leaves may also grow in misshapen forms that look like ferns.
Because the virus enters through cuts in leaves and stems, avoid handling the plant as much as possible.
So if you’re a smoker, wash your hands thoroughly with soap andwear garden gloveswhen working with tomatoes.
The temperature extremes destroy developing tomato blossoms.
Prevent blossom drop by using row covers to raise night temperatures.
Blossom-End Rot
Blossom-end rot is a common tomato plant disease that impacts the fruit.
It is brought on by a lack of calcium, usually brought on by fluctuating water availability.
It appears as a sunken, dead area opposite the stem (the blossom end of the fruit).
The area will expand as the fruit matures.
Prevent blossom-end rot by promoting steady, stress-free plant growth.
Water plants regularly to maintain moist but not waterlogged soil.
Spread a 2-inch-thicklayer of mulcharound plants to conserve soil moisture.
Presoak seeds to speed germination, and don’t plant them in cold soil.
Allow the top of the soil to dry between waterings.
Prevent sunscald by maintaining enough foliage to shade fruits or shade fruits artificially with a shade cloth.
Understanding the Tomato Plant Disease Code
Disease resistance has been bred into many tomato varieties.
