Prevent Tomato Diseases in your Home Garden
Growing healthy tomatoes isn’t rocket science. You just need to follow some common-sense prevention tactics to prevent tomato diseases.
Solarize your soil
Solarize your soil to control nematodes. It’s also an effective treatment for other pests and disease pathogens. Moisten the area and cover it with a clear plastic tarp. To be effective, it must remain in place for at least three to four weeks during the hottest part of the summer.
There are plenty of half-understood stories about marigolds out there. The myth is that planting marigolds around your garden will keep away pests. The truth is that spider mites love marigolds, and so do many rabbits, so putting in a few flowers might attract more pests than you had before.
The other part of the truth is that marigolds can be used to treat soil with nematode problems if you do it properly. You’ll want to select a French variety such as ‘Nema-gone’, ‘Golden Guardian’, or ‘Tangerine’. Plant the entire affected area thickly in the marigolds, grow them for at least three months, and then till them into the soil.
Rotate Your Crops
Put your tomatoes on a three-year rotation schedule. This will give you a chance to solarize your soil and break the disease cycle. Make sure that you don’t plant your tomatoes in a place that other members of the tomato family (eggplants and peppers) have grown in the past three years.
Dispose of Diseased Plants
Don’t compost plants with diseases because you risk spreading the disease to the rest of your garden. Throw away or burn diseased plants and any garden debris (mulch, weeds, etc) that came in contact with them.
Plant Disease Resistant Cultivars
For a list of cultivars, check out our article on disease-resistant tomatoes. Hint, hint, you can click on the link in Related Articles to go straight to the list of Pests and disease categories.
Symptoms That Are Not Tomato Diseases
(Or Really Problems, For That Matter)
Some tomatoes are like mutts: nothing to look at, but great to have. Some unimproved old-time varieties end up with “green shoulders.” That’s just the way they grow, and there’s not much you can do about it.
Many cherry tomatoes crack after heavy rains (or even if you look at them sideways), and there’s not much you can do about that, either. Just remember to pick all the ripe ones before it rains. Some kinds of big tomatoes are prone to cracking, too. These cracks typically scar over and do not affect the taste. Keep notes on which ones do well for you, and ask yourself, “Do I want perfect red balls that were bred to bounce well in shipping, or do I want real tomato flavor?”