Connecticut Garden Journal: Rescue Your Tomato Plants!

Jul 20, 2017

Ahh, the dog days of summer. This time of year you can almost see the corn, melons, and tomato plants growing. But along with all this lush growth comes problems, especially with tomatoes.

There are a number of leaf diseases that effect tomato plants. Early blight, late blight, septoria leaf spot, and bacterial speck are just some of the problems that plague tomatoes.

Some of these start innocuously as small yellow spots on the bottom leaves. With time, humidity, and heat those small spots expand into blotches and eventually the leaves and sometimes fruits get infected. Not only does this make the plant look ugly, it reduces yields.

Of these diseases, late blight is the most worrisome. It starts as water-soaked brown lesions on leaves and stems and quickly spreads throughout the plant. It's highly contagious to other tomatoes and potatoes so the entire plant has to be removed and destroyed.

Also, remove any volunteer tomatoes and potatoes each spring. Check with Connecticut Master Gardeners if you think you have late blight. For the other diseases, sanitation, resistant varieties, and sprays are the best options to preserve your tomato crop. 

Mulch under tomato plants, remove the bottoms leaves, even if they look healthy, space plants further apart and keep plants well watered trying not to wet the leaves. Spray Actinovate, Streptomyces lydicus, or a copper spray to prevent the disease from spreading.

Next year look for resistant varieties such as Iron Lady, Mountain Magic, and Defiant. If you get on top of these diseases now before they spread, you can keep your tomato plants producing luscious fruits until fall.

Next week on the Connecticut Garden Journal, I'll be talking about hardy hibiscus. Until then, I'll be seeing you in the garden.