|Issue #370 - July 12, 2012|
Identifying and Treating Tomato Diseases
Late blight has been spotted in Maine! Fast-spreading diseases like blight can be serious problems for the home gardener, especially when it comes to tomatoes. Below you'll find details on two of the most prevalent afflictions. If you see signs of these diseases or have any questions, feel free to contact our garden professionals right away.
Potato Late Blight is the same disease that caused the great potato famine in Ireland during the 1800's and will also affect tomato crops.
Symptoms of the disease include a water soaked grease spot on foliage or dark brown, almost black spots on the stalks or fruit (more photos here). Spores from infected plants can travel up to 40 miles in the air under the right conditions, so the Maine Department of Agriculture asks gardeners to destroy infected plants by burying or bagging them. This will prevent the spores from releasing in the air and spreading the disease.
For plants that have not been infected yet, the application of an organic fungicide is strongly recommended. You'll find a wide selection of fungicides to choose from here at Estabrook's. After applying the fungicide, continue to monitor your plants for signs of infection.
Extended periods of wet weather can produce Blossom-End Rot, a tomato disorder that is caused by low levels of calcium. When too much water is applied to plants, the roots are deprived of oxygen and unable to produce the calcium they need for normal cell production.
Blossom-End Rot usually begins as a small water-soaked area at the blossom end of the fruit. This may appear while the fruit is green or during ripening. As the lesion develops, it enlarges, becomes sunken and turns black and leathery. In severe cases, it may completely cover the lower half of the fruit, becoming flat or concave.
Protecting your tomato plants from overwatering and stimulating calcium production should be your focus. Apply a treatment of lime to help regulate the soil's pH and encourage calcium production, then mulch around the plants to keep soil moisture levels as consistent as possible.
Appropriate watering is extremely important to the health and beauty of your plants, especially in the heat of summer.
At Estabrook's, we recommend deep waterings 2-3 times a week even when it rains. Although it might appear that your plants are getting plenty of water in heavy rain storms, most plants will shed rainfall like an umbrella, leaving the root system dry.
When to Water
The best time of day to water is in the early morning before the temperatures begin to rise. This gives the plants a good supply of water to face the heat of the day. Early morning also tends to be a time of lower winds and thus reduced evaporation.
If watering cannot be done in the early morning, very late afternoon is also satisfactory. It is important to water early enough so that the leaves have time to dry before nightfall to avoid development of fungal diseases. If possible, choose watering methods that will not wet the leaves (such as soaker hoses) and thus allow for late evening watering.
What to Use
There may be need to evaluate the device used for watering. While a lawn sprinkler may be a good method for the lawn, it may not be the best way to water a garden. Pick a watering device that matches the needs of your garden and the time you have available to water. Once a device is selected, know the correct way to use that device in order to water efficiently.
|Estabrook's - Open 7 Days a Week - (207) 846-4398 - www.estabrooksonline.com|