The exotic flowering and fruiting passionflower vine makes an arresting statement when grown indoors as a decorative houseplant. Provide a growing space brightly lit with direct or indirect sunshine. Garden solariums, sun rooms, greenhouses or near large windows is an ideal spot. Less light is tolerated by the plant but bloom will also be diminished. Passionflower vine should be grown over a form to support its climbing habit and will make a large plant fairly quickly. Ideal culitvars for indoor planting include passiflora caerulea a blue version, Constance Elliot a white flowering version and passiflora coccinea a deep reddish orange to purple blooming version.
Select a growing site for you passion flower that affords bright indirect light for at least six to eight hours per day or bright direct sunlight for at least four hours per day, year round. In warm climates or during the heat of summer protect the plant from scorching by minimizing the midday direct sun exposure or by sheltering outdoors.
Provide ambient growing temperatures between 50 and 66 degrees Fahrenheit. The cooler end of the spectrum is preferred in winter. When kept at warmer temperatures the vine may look less vigorous and spider mites can become a problem.
Prepare a planting container at least three times the diameter of the root ball of a young plant and at least twice the diameter of a mature plant. Ensure adequate drainage holes in the bottom of the container. Re-potting should be minimized to every two to three years so the larger the pot the better. Fill the container one third full with fresh sterile potting mix and compost. Place the root ball in the container and back fill with potting soil and compost.
Water in deeply until drenched at planting time maintaining an evenly moist but not wet soil until the end of August when you can scale back watering to allow the first three to four inches of soil to dry out before watering again.
Feed your passionflower vine twice per month with a complete, balanced fertilizer that is water soluble such as a 20-20-20 formulation or twice a year with a slow release granular formulation. Follow package dosing directions and always err on the side of feeding less over more.
Provide a sturdy structure over which the vine can climb. Wall mounted wires, netting, tuteurs, topiary forms, hoops or spires all work to ensure good sunlight penetration into and air flow through the plant.