By Haley Mitchell Godwin

Tomatoes are one of the most popular plants in vegetable gardens, but they can also pose a significant challenge to growers. Disease, insects, and weeds are common problems that can affect tomato plants and reduce their productivity. To help local gardeners overcome these challenges, Neil Kelly, a Regional Extension Agent with the Alabama Extension Agency, conducted a class on tomato care at the Tom Harbin Ag Center on June 6. With tomato season well underway in south Alabama, Kelly stressed the importance for growers to maintain a “proactive” approach to disease, insect, and weed management.

“Every gardener, backyard growers and commercial farmers, encounters a wide variety of challenges when it comes to tomatoes,” Kelly said. “It can be almost like the tomatoes are looking for a way to die. Weather fluctuations, garden insects, environmental disorders, as well as viral, fungal, and bacterial issues can ruin a crop and it is easy to get busy and fall behind on management of your tomatoes. However, being proactive and aware of potential problems before they arise is the only way to make sure your backyard tomatoes thrive.”

Kelley offers the following guidelines to maintain the health of plants:

Watering and Mulching
To ensure proper watering, Kelly advises using drip irrigation or hand watering in the mornings, directly onto the soil surface, avoiding wetting the leaves as much as possible. Additionally, it is recommended to remove lower branches of tomatoes that come in contact with the soil and apply mulch. Mulching helps maintain consistent moisture levels, preventing issues like blossom end rot and acts as a natural weed control method, especially for insects that hibernate during winter, while also reducing competition for applied fertilizers. Moreover, mulch acts as a barrier between plant leaves and the soil, minimizing fungal problems originating from the soil’s surface.

Monitoring for Disease and Insects
Prompt action is crucial when dealing with insects or disease. As soon as yellow or brown spotted leaves appear, Kelly suggests removing them immediately. If a fungicide plan is not already in place, he suggests initiating a fungicide application to prevent early blight. Kelley emphasizes that early blight is a common issue faced by tomato growers and recommends applying preventive fungicides when the plants are healthy and disease-free. Fungicides containing chlorothalonil and mancozeb are effective against early blight. Copper can be used to control bacterial problems.

One should thoroughly inspect the plants daily for pests like armyworms, fruit worms, hornworms, and stink bugs, as they are the primary insect-related challenges for tomatoes. When dealing with young worms, products containing Bacillus thuringiensis (Bt) are recommended. Carbaryl-based products can be used for larger worms, while bifenthrin is effective against stink bugs and other common garden pests.

When selecting tomato varieties for Alabama gardens, Kelley said it is important to think about disease resistant varieties. While no tomato is resistant to all diseases, growers can choose varieties that exhibit resistance to specific problematic diseases in their region. Certain tomatoes are resistant to diseases like fusarium wilt, verticillium wilt, root knot nematodes, and tomato spotted wilt virus.

Some varieties show resistance to early blight, late blight, gray leaf spot, tomato mosaic virus, tobacco mosaic virus, bacterial speck, and bacterial wilt.

Additionally, considering the intended use of tomatoes is essential when choosing the right variety. Generally, tomatoes can be categorized into three types: slicing tomatoes, paste tomatoes, and salad tomatoes. However, opinions may vary on which varieties are best suited for each purpose.

Some individuals prefer using traditional slicing tomatoes for canning, while others opt for canning tomatoes for slicing. Popular slicing tomato varieties include ‘Better Boy,’ ‘Celebrity,’ ‘Crista,’ ‘Big Beef,’ and ‘Mountain Majesty.’ For paste tomatoes, smaller varieties such as Roma, Plum, and Mariana are excellent choices due to their lower water content and higher meat-to-water ratio. Salad tomatoes typically consist of grape and cherry varieties, known for their small size, bite-sized nature, and sweetness.

For more information or questions regarding these topics, please contact your local extension agent at 334-335-6312 or visit aces.edu.