What happened? Yesterday, your plants looked lovely. Today, several leaves are rolled up, looking like green cigars. What did this, is it a problem, and what can you do?
Physiological causes of leafroll
Leafroll (or leaf roll) can indicate environmental problems, such as water stress, too much nitrogen, drought, excessive heat, root damage, severe pruning, overspray, or transplant shock. Moderate upward cupping is usually first seen in lower leaves, spreading inward and upward, as the cupping progresses into a full blown leafroll. Leaves affected by these physiological conditions will thicken and become leathery as the plant tries to protect itself. This response is common to members of the nightshade family. Luckily, it has very little impact on fruit production or quality of tomato, eggplant, or pepper plants.
Leafroll is also a family of viral diseases that can infect many different plant species. These viruses enter plant tissue as their insect carriers feed. These carriers are normally aphids, mealybugs, and soft scale insects. The leafroll virus can also be spread through infected scion wood. Once infected, vascular bundles become clogged as the viruses reproduce in the nutrient-rich phloem. This reduces water and nutrient flow within the plant, causing stunting, delayed maturity, reduced crop size, chlorosis, necrosis, leaf curling, and leafroll.
There are three major types of leafroll that warrant concern:
Because these viruses can spread rapidly, over relatively great distances, close monitoring and control are in everyone’s best interest. Once a plant is infected with one of the leafroll viruses, it should be removed and destroyed. There is no cure or treatment. When shopping for plants, choose resistant varieties, and be sure to control carrier pests, to reduce the likelihood of leafroll affecting your garden.
You can grow a surprising amount of food in your own yard. Ask me how!