Passion flowers (Passiflora spp.) are exotic-looking flowers that are native to the United States, as well as South America and Australia. Passion flowers grow on vines, which are vigorous plants that can clamber up to 30 feet in one season along a trellis, arbor or another support. In order for passion vines to grow healthy and lush-looking plants, they need regular, yearly prunings.
In late winter, when passion vines are dormant and not actively growing, is the ideal time to prune them. An annual pruning helps train them, encourages fuller growth and prevents them from invading nearby spaces.
If your vines start growing before you had a chance to prune them, don’t fret. You can also prune passion vines annually in the early spring just before new growth or after new growth begins to grow.
During active growth, newly planted vines should ideally be allowed to grow to their fullest potential that first season. However, if they or older vines are imposing in unwanted areas, such as up trees and shrubs, and are getting out of control, you can prune them anytime.
Disinfect tools with rubbing alcohol after cutting other plants, including other passion vines, to help prevent the spread of any possible diseases. Cut off all the dead and thin wood and leave a few strong, well-budded stems. Do not cut passion vines to the ground like you may for other vines. Fertilize passion vines after pruning in the late winter or early spring with a low analysis balanced fertilizer, such as one labeled 6-6-6.