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
LB – Late Blight
Scientific Name: Phytophthora infestans
Type: Oomycete
Late Blight is a fungal disease that affects the growth of potatoes and tomatoes. Symptoms include large dark brown blotches with a green gray edge on the leaves resulting in large sections of dry brown foliage. Stems become dark brown. Dark brown circular spots cover most of the tomato. The entire field turns brown and wilted as if it was hit by frost and die.It can cause significant yield loss and even total crops losses. The diseased tomatoes are usually unmarketable. Late blight was responsible for the Irish potato famine of the late 1840s. The air-borne disease can destroy an entire field in a short period of time. The infected plants should be removed and burned to avoid further infestation. If you stick with Late Blight resistant tomato varieties you don’t have to worry. The disease is favorable when temperatures are 60-70 F and usually occur when moisture and humidity are very high. Plan on using a 3 year crop rotation and avoid planting in the same location, year after year, as the disease can survive in the soil for 7 years. Fungicides are available for management of late blight on tomatoes. The best option is to use disease resistant varieties.