Common Tomato Diseases

If you cultivate a vegetable garden, you may plan on planting a crop of tomatoes. In order to grow ripe, healthy tomatoes for your friends and family, you need to know how to recognize common tomato diseases. Recognizing a tomato disease early may allow you to take action in enough time to protect the rest of your tomato crop from the same fate.

Fusarium Wilt

Fusarium wilt is caused by the Fusarium fungus. The leaves of a tomato plant infected with the Fusarium fungus will turn yellow and wilt. This is due to the fact that the fungus inhibits the tomato plant’s ability to absorb water and nutrients. Many gardeners who are unfamiliar with Fusarium wilt mistake it for a lack of water. This may be a costly error. If infected plants are not immediately removed from the garden, other plants may quickly become infected with the Fusarium fungus.

If you suspect that one of your tomato plants suffers from Fusarium wilt, cut into the stem near the base of the plant. The inner stem of a plant that is infected with the Fusarium fungus will have a brown hue. There is no cure for Fursarium, but some varieties of tomato, such as the Roma tomato, are naturally immune to damage from the fungus.

Tomato Spotted Wilt Virus

Tomato Spotted Wilt Virus (TSWV) initially manifests within the tomatoes themselves rather than the leaves or stem. TSWV is characterized by yellow or brown rings on the tomatoes that gradually progress to a black rot. The rot is most commonly seen on the area where the tomato attaches to the plant itself, however, the rot may appear on any part of a tomato.

Currently, the only treatment available for TSWV is to remove infected plants from the garden. The virus spreads by way of insects, which can be difficult, if not impossible, to properly control in an outdoor environment. TSWV can infect over 300 different varieties of tomato plants. Pesticides have proven to be ineffective at treating or preventing TSWV.

Septoria Blight

Septoria Blight is a fungus that appears on the leaves of infected tomato plants. The fungus causes numerous tiny brown spots or holes in the leaves of the plant and is often mistaken for insect damage.

If you suspect that one or more of your tomato plants is suffering from Septoria Blight, it is not necessary to remove them from the garden, as the tomatoes themselves will be unaffected by the fungus. Because the fungus is spread most easily by water, water your tomato plants only when the wind is low. This prevents wet, infected plants from coming into contact with healthy plants. Spacing your tomato plants well also goes a long way toward preventing Septoria Blight.

Keep in mind that although the fungus itself does not directly affect the tomatoes, it can have an indirect effect on their health. As the fungus eats away at the leaves of the plant, the leaves slowly die and fall off. This leaves the tomatoes with less protection from the sun. Tomatoes that do not have adequate sun protection may end up with sunscald and be inedible.

Raising tomatoes is especially rewarding for amateur gardeners, who can see the fruits of their labor in as little as three months. If you plan to grow tomatoes, it is vital that you familiarize yourself with common tomato diseases and know how to treat them in order to keep as many tomatoes as possible healthy and edible.