Purple Passion Plant Leaves Curling and Turning Brown

Drought

• Inadequate irrigation and direct sunlight contribute to curling, brown leaves on this plant. Because purple passion plant is only suitable for a limited range in U.S. Department of Agriculture plant hardiness zones 10 to 12, it is most commonly grown as a houseplant. You should grow it in a sunny location with filtered or indirect sunlight to avoid scorching the leaves. Water regularly to keep the soil moist. You can reduce watering slightly in the winter, but don't allow the soil to become bone dry.

Disease

• Botrytis blight is a fungal disease that can discolor leaves, causing them to yellow, turn brown and wilt. The plant may produce flower buds that rot or fail to open. If you see masses of grayish brown spores on wilted areas, it's a sure sign you are dealing with blight. To treat the plant, remove and destroy dying plant tissue and avoid overhead irrigation -- the disease favors moist conditions. Do not compost with infected leaves.

Pests

• Spider mites are tiny insects that thrive in hot, dry conditions, often attacking plants that are stressed from lack of water. Damage may initially appear as a stippling pattern on the leaves. Eventually, leaves may turn bronze and drop off. The presence of spider webs is a telltale sign. Remove spider mites with a direct stream of water or by applying insecticidal soap to the undersides of leaves. Do not use insecticidal soap on drought-stressed plants.

Prevention

• A healthy plant is less likely to succumb to pests and diseases. The purple passion plant prefers a well-draining, moist soil mixture. Cal Lemke, former botany greenhouse grower for the University of Oklahoma, recommends mixing 2 parts peat moss with 1 part loam and 1 part sand or perlite. Fertilize the plant every week during the growing season with a 10-10-10 fertilizer diluted by half of the label's recommendation with water. You can cut the leaves back in the winter to a height of about four stem nodes; this allows the plant to produce new, fresh growth in the spring.