Passion vine is one of the more attractive blooming plants. Their complex flowers are brilliantly colored and often lead to edible fruits. Passion flower leaf loss can be the plant’s response to a host of things, from insects to cultural incompatibility. It could also simply be zonal or related to the time of year. Some clues regarding leaf drop on passion vine will help us sort out the causes and solutions.
Why is My Passiflora Losing Leaves?
Passion flower is an intricate blooming plant whose flowers were used to teach the Stations of the Cross. Several varieties are native to North America and many are hardy to USDA zones 7 to 10. Some varieties are tropical and not frost hardy, causing them to lose leaves during cold snaps and often die. If you find a hardy passion vine dropping leaves, causes may be fungal, insect related or cultural.
Any time a plant experiences unusual conditions such as leaf drop, the first step is to look at its requirements and ensure they are being met. These plants need consistent water but well-draining soil, especially during flowering and fruiting.
Moderate feeding is also a good idea, to promote strong root systems and promote blooms. An early spring feeding of 10-5-10 fertilizer should be applied just before new growth appears and followed by consecutive feedings every two months during the growing season. While this may not prevent passion vine dropping leaves, it will promote the formation of new foliage.
Disease and Leaf Drop on Passion Vine
Several fungal diseases can cause passion flower leaf loss. Among these, Alternaria leaf spot is one of the more common. This disease affects many types of plants, especially fruiting varieties. It not only causes Passiflora leaf drop but also necrotic fruit.
Anthracnose is another common disease. It stems from a fungus that attacks the edges of leaves and eventually stems. There are several fungicides that can be used to prevent the disease but once the fungus has taken hold, plants should be destroyed and a cultivar that is grafted on yellow passion vine rootstock should be planted.
Fusarium stem canker and Phytophthora root rot begin at the soil line and will eventually lead to leaf drop on passion vine. There are no EPA registered products for control of these diseases.
Passion Vine Dropping Leaves Due to Insects
The most common reason for a passion flower dropping leaves is through insect activity. Spider mites are very active during hot, dry periods. They are very tiny and difficult to see, but the webs they leave behind are a classic identifying characteristic. These insects suck the sap from the plant, both on the leaves and the stems. Reduction of sap will cause leaves to wilt and drop. Keep plants well watered and use a horticultural oil.
If there are brown sticky spots on leaves, the problem could well be aphids. They secrete honeydew, a substance that will also attract ants. These are also sucking insects that can adversely affect plant health. Insecticidal soaps and horticultural oil, such as neem, are effective. You may also simply blast them off with water. Provide extra care for the plant as it recovers from any insect invasion.