Where can this tropical gem, the Passion flower, be crowned? It flourishes in the glorious sunshine of the tropics and in locations where winter temperatures reach 20° degrees Fahrenheit below zero and even lower, as it does here in Minnesota.
From experience, I have found that the passion vine can actually be grown and enjoyed here during the entire 12 months of the year. There is no dormant interval since a succession of plants is propagated.
My first introduction to this vine was in Berkeley, California, where I found it covering a large pergola in the backyard of our parsonage.
Naturally, I was fascinated by the intricate structure of the blooms. However, once this flower is seen, it is never forgotten. To me, mere words cannot describe the rare beauty of the passion flower.
A Pleasant Discovery
Realizing that this vine grew well in California and some of the southern states, I was unaware we could simulate its needs here.
However, I was astonished one day when I saw this vine covering the whole wall of a Minneapolis residence. A generous friend shared cuttings of the plant (Passiflora caerulea) and explained its cultural requirements.
Since then, it has been great fun reviewing the available literature and checking seed lists in catalogs of rare plants.
The Passifloraceae Family
The Passifloraceae include probably 250-300 species. Most of the cultivated kinds are vines, climbing using sturdy tendrils.
The foliage is attractively lobed or parted on most species, and the flowers are primarily axillary. The standard colors are blue, yellow, red, white, or pink, and the hybrids produce various shades of these colors.
Some species produce edible fruits of varying sizes, 8″ inches long and down to hen’s egg size. Some are oblong, and others are round as a ball.
The fruits contain many seeds surrounded by gelatinous pulp and subacid juice, which is used as dessert flavoring or eaten directly from the fruit with a spoon.
The thin, brittle shell of ripe fruit is yellow, green, or purple in color.
Purple Granadilla’s Fruit
The fruit of Passiflora duties, referred to as purple granadilla, is the size of a hen’s egg and has a pleasing flavor.
It is cultivated extensively for its fruit in Australia. There, the vines continue in profitable production for 4 to 6 years, after which they are renewed.
This species usually fruits prolifically and will often produce fruit in pots when one or two years old. The fruit is dull purple when ripe.
Passiflora Quadrangularis
Passiflora quadrangularis has 8” inch fruit and is popular in Costa Rica, Brazil, and Cuba. It is becoming widely known in other tropical regions as well. A missionary friend said this species was one of his favorite fruits in India.
The passion vine is fast becoming a collector’s item with gardeners because it is so easily propagated by seed or cuttings.
Six to 8” inch, well-matured cuttings are made during August and rooted in water, sand, vermiculite, or sponge rock (Pearlite). Each cutting is taken directly below a leaf axil, and all foliage that would be submerged is removed.
The roots usually develop at the lowest leaf axil near the base of the cutting. If only one or two cuttings are needed, they may be placed in a colored bottle in a cast window.
The Right Time To Transplant
These are potted after the roots are 3” to 4” inches long. If potted sooner, the sources do not seem able to feed the semi-woody stem, and a subnormal plant may result.
It is also possible to continue growing the cuttings in water all winter. They will bloom, though not generously, and the foliage will not be as lush, even though complete food is added to the water.
Here we grow the vines in sandy loam, but they grow as successfully in other soils that are not too heavy. Leaf mold is also added to the earth, especially in the potting soil.
The seeds used for propagating should be well-ripened and dried. Plant while fresh in light soil. The sources are almost as large as a small popcorn kernel and are slightly flattened.
Germination requires several weeks, and the seedlings are easily raised in good light with some sunshine. They will bloom when they are six months old.
My experience needs to be more extensive to know if the blooms on seedlings always come true to color. For example, last year, I grew some from seeds gathered in Arkansas, and my blooms were pure white, while the flowers on the mother plant had a definite pinkish tint.
The rays on the corona were crimped on the margin, which is somewhat unusual because the fringe-like filaments or rays in most species are straight.
I like to plant the seeds in December or as early as possible to secure the new source to be assured of the summer blooming outdoors.
The vines are set in open ground in April or May as soon as the danger of frost is over. Those from cuttings, rooted in August, begin to bloom in the window garden in December and continue flowering in pots until planted out for the summer.
Feeding Is Important
Plants appreciate ample fertilizer worked into the soil or applied in liquid form. While they can be grown in large pots outdoors for the summer, they will require more care in supplying moisture and protecting the pools from intense heat. Yet, they will bloom and bring great satisfaction as pot plants.
When grown in pots, a trellis is needed, and growth can be cut back when it needs to be renewed.
Each year, I plant three vines in each of two groups where they cover a trellis on the west end of an attached garage. The tendrils cling tightly without any help.
The only assistance they may need at times is to guide some of the more vigorous shoots to stay within their allowed space.
Since the cement drive is connected to a cement walk, the vines on one corner of the garage are planted in a large homemade box that fits the space available.
While the vines are grown more vigorously in the open soil, the box method solves our problem well.
The vines would cover a giant trellis if provided. By pruning the tips, they branch more freely. We usually plant several colors together for added interest. They seem to bloom even more freely out in the open, away from a hot wall.
Our Favorite Blooms
In our collection, the one with the favorite bloom is Passiflora x alato-caerulea, a hybrid between Passiflora alata and Passiflora caerulea.
The 4” inch flower is pink, blue, purple, and white, and the fragrance is delightful. 11 has large, three-lobed foliage.
Perhaps the species with the most exciting foliage is Passiflora “maculifolia.” Its variegated foliage is green with silver bands, generously marked in pink and yellow, with purplish tones beneath the three shallow-lobed leaves.
A red-flowered form with slender, three-lobed foliage, grown from Australian seed, maybe a hybrid. Also, a thin, five-lobed type, with rose-colored veins beneath the leaves from the same source, may be of hybrid origin.
Passiflora edulis has large, three-lobed foliage with flowers of purple and white. I anticipate ripened fruit in the window garden if our summer is too short to ripen the fruit on the trellis.
Some years we have frost here in September, and in other years, only in November. Several fruits were full-grown last fall, but Jack Frost gathered them before they ripened.
Reason For The Name
The legend connected with this unusual flower stems from the imaginative Spanish missionaries. When they discovered this flower in America, they associated its rare structure with the Passion of Christ.
The numerous, thread-like filaments, extending from the center of the bloom, represented to some the crown of thorns and to others the halo around Christ’s head.
The 10 petals depicted the 10 disciples present at the Crucifixion, with Judas and Peter absent.
The five anthers typified the five wounds and the tendrils of the vine, the whips.
The stamens, pistil, and other parts of the bloom also had their significance. This legend suggested both the common and the scientific name — Passiflora.
This vine can be grown where it receives a great deal of sunshine, but the flowers remain open longer on cloudy days, which should mean that an east exposure may be preferable.
Each flower remains open for one or two days, and new ones appear daily, keeping the color display constant.
When freshly cut, the blooms make a beautiful centerpiece for a day or evening. When the flower closes, the outer petals fold up and conceal all the intricate beauty of the center.
However, if hot candle wax is dropped at the base of the petals to prevent them from closing, they may be enjoyed throughout the evening.
Some species are reasonably hardy if planted in a sheltered location in a southern exposure near the foundation of a house and are well mulched during the winter.
Reports of laying the vine on the ground and covering it well have been successful. However, if in doubt about the hardiness of the species you are growing, it is advisable to root cuttings and carry them over winter indoors.
44659 by Florence Knock