Fight Tomato Late Blight With a Trellis

Tomato late blight (Phytopthora infestans) is a fungus that creates brown or black lesions on your prized tomato plants. The lesions begin on leaf veins and can spread like wildfire over the plants. Moisture is a prime culprit in spreading it.

Trellising your tomato plants is one good way to dodge this disease. Now is the time to install your tomato trellis.

Here’s why it works: a trellis and proper training allows air to circulate around and through the plant, letting the leaves and stems stay dry.

Tips:

• A trellis will give your plant something to climb on, which is especially useful for indeterminate (vining) tomatoes, which can become a dense, tangled mass that traps moisture. 
• Train your tomatoes by loosely tying stems to the trellis. This will help you ensure that air can circulate.
• Prune your indeterminate tomatoes to 3 or 4 main stems to make it easier to trellis. With less competition, your tomatoes may be larger and ripen more reliably.
• Determinate tomato types, which have a bush habit, can be contained fairly well with the average wire tomato cage but still need air circulation.
• Avoid moisture on the leaves from overhead watering by applying water at the base of the plants.