Passion flowers are generally quite easy to care for. If you have chosen a suitable location and are planting in the ground, you can likely almost forget about them once they are established.
They prefer full sun, but most will tolerate partial shade at the expense of producing fewer flowers.
Provide them with plenty of water, particularly during hot weather, however do no let them stand soaking wet as they can be susceptible to root rot. If grown in a container they may need watering more than once a day during hot weather as it is best to avoid letting them wilt.
Feed them with a good quality fertilizer designed for blooming plants during the growing season. 5-8-4 or a similar multipurpose fertilizer is ideal. Make sure the fertilizer is for blooming plants as too much nitrogen will produce excessive leaf growth at the expense of blooms. Liquid, granular, or slow release fertilizer are all suitable.
Passion flowers are quite tolerant of a variety of soil types and infertile soil. If planting in a container, use any, well-draining potting mix. It can be either peat or bark mulch based as the plants do not care. If planting in the ground just make sure the area is well drained.
At the end of the growing season if you wish to overwinter your vines, non-hardy passiflora will need to be brought inside to protect them from the cold. They can be cut back significantly to reduce their mass to bring them in. Make sure you do not cut off all of their leaves, and that you reduce watering proportionally to the amount of material cut off. Place them in a greenhouse or a sunny window for the winter months and water when they get dry. In the spring gradually transition them outside. To avoid burning the leaves, either place them in the shade, or outside for only a few hours at first then gradually move them to a sunnier location.
If you live in a warmer climate or are growing a hardy passion flower planted in the ground, cut back the tops of the vines to the ground once killed by frost, and mulch the roots (particularly if your vine is marginally hardy in your zone). In the spring they should resprout.
Hardy passion flowers planted in containers will need winter protection in colder zones. Either bring them inside to a frost free area, or plant the whole container into the ground to protect the roots over the winter.
Make sure you select a suitable trellis to grow your passion flower on. Passion flowers have tendrils and need small wires or strings or stakes that they can wrap their tendrils around. Bamboo stakes tied in a teepee, or wire fence work well.