AUBURN UNIVERSITY, Ala. — Tomatoes are by far the most popular plant in the vegetable garden, but they can also be the most problematic. Eliminate the questions and begin the official summer season with proper tomato care.

Weather, insects and viral, fungal and bacterial problems are all challenges every gardener faces when growing backyard tomatoes. Having an awareness of potential problems before they arise is one way to make sure the backyard tomatoes thrive. Mallory Kelley, an Alabama Cooperative Extension System home grounds, gardens and home pests regional agent, said there are many things to watch for when growing tomatoes to ensure a healthy crop. As the hot and humid summer starts up, Kelley provides the following tips to keep plants healthy.

Watering and Mulch

When it comes to water, Kelley recommends starting with drip irrigation or hand watering only at the surface of the soil to avoid splashing. Then, gardeners should prune off any of the tomato plants’ lower limbs that are touching the soil and apply mulch.

“Mulching your tomatoes keeps the plants moisture level consistent and will help prevent blossom end rot,” Kelley said. “Applying mulch also helps control weeds where insects like to overwinter and eliminates competition for the fertilizer you have applied.”

Mulch also creates a barrier between the plant leaves and the soil to suppress many of the fungal problems that come from the surface of the soil.

Scout for Disease and Insects

For diseases and insects, time is of the essence. Remove yellow and brown-spotted leaves as soon as they appear. If a fungicide plan is not in place, start a fungicide application to prevent early blight.

“No tomato grower can avoid this problem,” Kelley said. “It’s best to apply a preventative fungicide when the plants are healthy and there is no disease present. Products with the active ingredients chlorothalonil and mancozeb will control early blight.”

Kelley said copper is an option to control bacterial issues. It is best to scout daily for all of these problems, as well as insects.

“Go out and inspect for armyworms, fruit worms, hornworms and stinkbugs,” she said. “These are the main insect problems on tomatoes.”

Products that contain Bacillus thuringensis (Bt) will work when the worms are young, but Bt will not kill any other bugs. Gardeners can also use products containing carbaryl to control larger worms. Kelley said carbaryl will eliminate a wide variety of insects it comes in contact with—even larger worms if they ingest enough of it. However, the damage has been done by the time worms are large, so treatment may not be necessary. Bifenthrin is another insecticide that will control stinkbugs and some of the other pests gardeners may find.

“Don’t wait until your plant has no more leaves before you start your search for the hornworm,” Kelley said. “Scout today because the plant may not be there tomorrow.”

More Information

Want to learn more about what may be affecting tomato plants and what you can do to help tomatoes thrive? Call the Master Gardener Helpline at 1-877-ALA-GROW (252-4769) or reach out to the your county’s Extension office for more direction. You can also learn more about growing, canning and storing tomatoes through Alabama Extension’s many regional workshops. To find the next workshop near you, visit www.aces.edu and search tomato in the calendar.