Passion Flower Diseases

Viral Diseases

• Passion flowers are subject to viruses such as Passiflora latent virus, cucumber mosaic virus, three passion fruit viruses and several others. Plants produced by propagation -- as opposed to seed -- carry susceptibility to these viruses in their genes. Symptoms include poor overall development and leaf deformation. Helping the plant through the infestation with fertilizer can help. The best way to reduce future viral problems is to not take cuttings or divisions from the affected plant for propagation.

Bacterial Diseases

• Bacterial spot and bacterial grease spot both affect passion flowers. Bacterial spot appears as black spots on the leaves and, if left unchecked, will kill the leaf, causing it to turn brown and shrivel. Bacterial grease spot affects the fruit and manifests as a greasy dark lesion that eventually destroys the fruit. Both these diseases appear mainly in Australia and tropical areas. The best control is to plant a disease-resistant variety. If a plant does become affected, it should be removed. A new passion flower shouldn't be planted for at least a couple years in the same spot.

Fungal Disease

• Passion flowers are hit with the same fungal diseases as many other garden plants. These include rust, damping off, anthracnose and fusarium wilt. Some fungal diseases present as spots of red or gray on the leaves, suddenly dropping leaves, withering of stems and misshapen fruit. Besides growing fungal-resistant varieties, fungi are best controlled by not allowing plants to stay wet and to improve air circulation around the plant. Heavy cutting can also introduce fungal diseases to the roots. Affected portions of the plant need to be removed as soon as possible and destroyed. Several fungicides are available to help you with your battle.

Nematode Diseases

• Although some species of nematodes eat pests and help your garden, others will harm your passion flower. The Meloidogyne and Rotylenchulus species of nematodes both cause knots to form on the roots of passion flowers. These knots make it difficult for the roots to take in water and nutrients and the entire plant suffers from malnutrition. Symptoms include yellowing and drooping leaves and stunted growth. Planting healthy plants throughout your garden is the best preventative measure.