Care of Passion Flowers
- Passion flowers need to be planted where they will receive at least 4 hours of full sun a day. Southern gardeners need to place their plants where they will have afternoon shade. Northern gardeners to zone 6 need to plant their vines on a southern or western exposure for added winter protection.
Passion flowers can be planted in any well-draining soil with a neutral pH (6.1 to 7.5). Dig a hole slightly larger than the root ball. Add a handful of compost to the bottom of the hole before planting to make this heavy feeder happy.
With a height between 15 and 30 feet, passion flower vines need some sort of support. Plant your passion flower along a wall or fence or next to an arbor or trellis. Passion flower vines use tendrils to attach themselves to their support, so no tying needed.
Passion flowers need to be kept evenly moist and the roots need to stay cool. Their shallow root system can make this a challenge. Using organic mulch (straw, shredded bark or leaves) 2 to 3 inches deep around the base of the plant works to cool the roots during the summer and hold moisture. In spring use a commercial 10-5-20 liquid fertilizer or organic gardeners can work a handful of compost around the roots being careful not to disturb them. Fertilize every 6 weeks until late summer (mid August to early September). - Passion flowers flourish in containers as long as they have a trellis or other support to attach to. You can use any general potting soil for passion flowers, but the container needs to be deep enough that it won't tip over when the passion flower reaches its full height of 15 to 30 feet.
Fertilize as you would passion flowers planted in the garden, remembering to stop fertilizing in late summer. In the fall before the first frost date, move your plant indoors placing it where it will receive bright, indirect light.
Keep your plant evenly moist but do not let the soil get soggy. Use a water catcher under the pot and discard the collected water.
Your passion flower can go back outside in spring after all threat of frost has passed. Before setting your passion flower outside remove it from the container and replace half the soil in the pot with new potting soil. Mix the remaining soil in the container with the new potting soil and re-pot your passion flower. The old soil can be added to your garden or compost heap. You must replace at least half the soil as the passion flower's heavy feeding, even with added fertilizing, removes nutrients from the soil faster than additional fertilizer can add them. - Passion flowers make exotic houseplants and can live for years with proper care. Use a general purpose potting soil in a container 3 to 4 times larger than the root ball. Fertilize as you would passion flowers planted in containers and in the garden. Place your plant where it will receive bright indirect sunlight but will be out of drafts. Keep the room your passion flower is in above 50 degrees F.
Keep the soil evenly moist and mist the plant once or twice a month. In winter allow the soil to dry out slightly before watering. To keep your passion flower at a suitable height, prune the growing tips off the vines at the height you want your passion flower to remain. - Prune passion flowers in spring just after it starts growing. Make your cuts just above a node (the spot where leaves emerge) as new growth will emerge from the node. Remove all dead wood and pinch back side shoots for a bushier plant. To keep your passion flower at the height you want it, you can cut back the top at any time during the growing season.
In fall, cut container plants back to 2 to 4 feet tall to make moving easier. In frost-free zones you don't need to prune in fall, however, if you live in an area with frost or snow your passion flower will most likely die back to the crown. Remove the dead vegetation before settling the plant in for the winter. - Passion flowers do not grow well from seeds. It can take months before germination and the babies will not look like the parent plant and will have different characteristics like winter hardiness and flower color.
To start a passion flower from seed, clean the seed thoroughly and allow it to dry. Using a fine grit sand paper lightly score the outside of the seed coat. Place the seeds in a container of water and leave them for 1 to 2 days. Viable seeds will sink to the bottom; discard floating seeds. Use a sterile seed starting mix placing the seeds 1/4 to 1/2 inch deep. Place the potted seeds on a seed warming mat, on top of a refrigerator or anyplace where the soil temperature will be about 70 degrees F. Place the seeds in a bright spot out of direct sunlight. Keep them evenly moist. It may take 3 to 6 months before your seeds germinate.
You can also do root cuttings from your passion flowers. In mid spring or early summer take cuttings from the tips of vines leaving at least 2 leaves per cutting. Make sure the stem of your cutting is not hollow. If it is cut back to where the stem is solid. Remove the bottom leaf, flowers and tendrils and dip the cutting in rooting hormone. Place the cuttings in a 50/50 mix of sand/peat or sand/perlite. Place out of direct sunlight in a room where the temperature stays between 65-70 degrees F. Keep the cuttings moist. If they start to wilt even with moist soil make a tent out of clear plastic, using chopsticks to keep the plastic away from the cuttings. Punch several small holes for ventilation. - In frost-free zones passion flowers do not need special care over winter. In zones that have frost, snow or ice you will need to keep the crown from freezing. Your passion flower will die back to the crown after the first frost. Remove the dead vegetation and any mulch. Pile straw loosely to a depth of 3 to 5 inches over and around the crown. Remove the straw in spring after all danger of frost has passed. If you are growing passion flowers in containers simply move the container indoors. Place the container in a room that receives bright indirect light and stays above 50 degrees F. If you are using a garage or other outbuilding to overwinter your passion flower, wrap burlap around the plant to protect it from drafts.