Passion Vine Wilting and Brown Spots

The passionflower vine (Passiflora edulis) is known for its unusual purple flowers and the edible large, orange-yellow berries it produces. The flower has a fringe of sometimes wavy and crimped hairlike segments coming out from its center. The three-lobed leaves are dark green on top and whitish underneath. This plant grows in U.S. Department of Agriculture hardiness zones 9b through 11. Passionflower vine is susceptible to diseases that can cause it to wilt and have brown spots.

Brown spot is caused by the fungus Alternaria passiforae, which creates small reddish-brown spots on leaves of the passionflower vine. The higher the humidity, the larger the spots. Some growing to 3/4 inch. Spores appear as a black, thin mass in the center of the spots. Affected leaves drop off. Lesions on the twigs are elongated and may cause death at the ends on terminal portions. Sunken reddish-brown spots may also appear on the fruit. The disease spreads through wind, water splashes and infected seedlings. Help prevent the disease by watering at the base of the plant to prevent splashing water.

Septoria blotch (Septoria passiflorae) first appears as light brown spots on the leaves 1/4 to 1/2 inch in diameter. One lesion is enough to cause leaf drop. Lesions also appear on twigs, ultimately resulting in twig death and wilting. Flowers can also be affected with lesions similar to those on the leaves. Like the leaves, infected flowers will drop off. Affected fruits have circular lesions and fail to mature or develop properly. This disease flourishes in long periods of rain and mild temperatures.

Anthracnose (Gomerella cingulata) begins with light brown spots that later become brown. The spots become brittle in the middle, causing the leaves to break apart and in many cases, fall off the passionflower vine. On twigs, anthracnose appears as elongated brown spots that later become cankers, which can result in wilting and twig death. Affected fruit can have oily spots that later turn brown, sometimes resembling bruising. Infected fruit usually drops early. You may also see small black spots on the lesions. The flowers can become spotted and drop. As with most fungal infections, water plays a major role. Always water at the base of the plant and destroy severely infected plants.

Bacterial spot (Xanthomonae axonopodis) leads to small, dark green lesions with yellow margins that later grow into larger brown spots if conditions are favorable. Infected leaves typically wilt and drop off. The bacteria can also get into the veins, causing grooves and darkening along the veins. Lesions on the passion fruit are usually a dark brownish green. The bacteria also release exudate that forms a crust over the surface of the lesion. Remove affected leaves, fruit and other diseased parts to reduce infection. To further prevent disease, disinfect all pruning tools and keep plants away from wind and wet conditions.