BER - Blossom End Rot

Type: Physiological Disorder

Blossom End Rot is a physiological disorder that affects tomatoes. As tomatoes begin to ripen, black spots on the bottom of the tomato appear. The tomatoes affected by blossom end rot should be picked and discarded. The cause is a calcium deficiency. The condition is not caused by a lack of calcium in the soil, but because the plant is unable to take up the calcium that is already in the soil because of drought or erratic watering. It is most common when the growing season starts out wet and then becomes very dry when tomatoes are setting. Plants are unable to absorb calcium because the soil is too wet or too dry, there is excessive nitrogen in the soil, roots are damage during cultivation, soil pH is either too high or too low, cold soil, and high levels of salts in the soil. Keep consistent levels of moisture in the soil throughout the growing season. Allow soil to warm before planting. Use mulch, such as Red Tomato Mulch, to minimize evaporation and to help maintain consistent moisture in the soil. Test soil so pH is at 6.5. Use Tomato Rot Stop to prevent calcium deficiency. The best option is to use disease resistant varieties.

EB – Early Blight

Scientific Name: Alternaria solani

Type: Fungus

Early Blight is a soil-borne disease that affects the growth of tomatoes. This disease is most common in North America. The symptoms include collar rust on the stems, circular dark spots appear on the leaves, rings surround the spots with a yellow halo, and tomatoes crack at the stem. The leaves may die and fall off the plant resulting in extensive defoliation, exposing the tomatoes to sun scald. Black spots may appear on the tomatoes. The disease can cause substantial yield loss and total crop loss. It is spread by wind and water. The infected plants should be removed and burned to avoid further infestation. The virus can live in plant debris and in the soil. The disease is favorable when temperatures are 82-86 F and usually occur when moisture and humidity are very high. Plan on using a 2 to 3 year crop rotation and avoid planting in the same location, year after year, and can survive in the soil for 1 year. Fungicides can help manage the disease. Stake plants to improve air circulation. Use drip irrigation to keep foliage dry and avoid overhead irrigation. The best option is to use virus-free seeds and disease resistant varieties

F – Fusarium Wilt (Race 1)

Scientific Name: Fusarium oxysporum

Type: Fungus

Fusarium Wilt, Race 1, is a fungal disease that affects the growth of tomatoes. It is one of the most devastating of all soil-borne diseases. Race 1 is the most widely found throughout the United States, especially in warm regions of the country. It attacks the roots of the plants and moves up the stems. Symptoms include yellowing and browning of the older bottom leaves, stunting, and wilting. Often the entire plant will die. Usually little or no fruit develops. The infected plants will produce inferior and unmarketable tomatoes. It can cause significant yield loss and even total crops losses. If you stick with Fusarium Wilt Resistant tomato varieties you don’t have to worry. Many of the older heirlooms don’t have any resistance to the disease, so if you grow these then you should keep an eye out for it. The infected plants should be removed and burned to avoid further infestation. Plan on using a 5 to 7 year crop rotation and avoid planting in the same location, year after year, as the disease can survive in the soil up to 10 years. The best option is to use disease resistant varieties.

St – Stemphylium Gray Spot Leaf

Scientific Name: Stemphylium solani, Stemphylium floridanum, and Stemphylium botryosum

Type: Fungus

Stemphylium Gray Spot Leaf is a fungal disease that affects the growth of tomatoes. It is found in warm regions of the country, and is common in the Southeastern part of the United States. Symptoms include brown to black specks on leaves. As the lesions grow in size, they develop a gray center surrounded by a yellow area. The spots may dry and fall out, forming a shot hole in the leaf. The disease may cause the entire leaves to turn yellow, then brown, and drop off, and the plant may be stunted. The tomatoes are not usually affected unless there is severe defoliation, where sunburn damage can occur on the tomatoes. If you stick with Stemphylium Gray Spot Leaf Resistant tomato varieties you don’t have to worry. Many of the older heirlooms don’t have any resistance to the disease, so if you grow these then you should keep an eye out for it. The infected plants should be removed and burned to avoid further infestation. Plan on using a 5 to 7 year crop rotation and avoid planting in the same location, year after year, as the disease can survive in the soil for many years. Stake tomato plants for better circulation. Give plants extra space to allow air to move among leaves to keep leaves as dry as possible. Use soaker hoses and avoid overhead watering. The best option is to use disease resistant varieties.