Passion flower are rambling, tropical vines with showy, fragrant blooms. The blooms come in many colors and typically have a broad circle of 10 leaves with raised white or pink filaments in the center. Passion flowers thrive in warm, moist conditions, and most are hardy to zone 9 or 10. Nebraska lies in USDA hardiness zones 4 and 5. Passion flower are only grown in the state as an annual or overwinter indoors.
Plant Passion flowers outside after the last expected frost in a hole the same depth, but slightly wider than the potted plant. Add 1-to-2 inches of compost to your soil to combat Nebraska's alkaline or clay soils. The flower should be planted in a sunny but sheltered area. Mulch with 2 inches of wood chips to preserve moisture.
Water the flower at least once a week to keep the soil evenly moist. Water more if the soil is dry 2 to 3 inches below the surface. Adjust your watering schedule during hot, windy weather and water more if your Passion flower is in a pot. Fertilize the flower every three to four weeks with a liquid fertilizer made for flowers.
Plant the flower 6-to-12 inches from a fence, trellis or wall. Passion flowers climb to a height of 12 feet or more in the space of one summer, depending on the species. They will attach themselves to the nearby object through tendrils.
Bring the passion flower indoors when the first frost threatens. Cut the plant back hard to 6-to-8 inches tall and keep it in a cool place so it remains dormant for three or four months. Water it every three or four weeks to keep the soil slightly moist.
Place the Passion flower in a warm, bright location when March arrives. Water it once per week until it's thoroughly moist and fertilize it every three or four weeks with a liquid fertilizer made for flowers.