Among the seasonal holiday plants on the crowded shelves in my local supermarket are a few pots of white stephanotis vine (Stephanotis floribunda, syn. S. jasminoides), sometimes called Madagascar jasmine. It’s a lovely vine, with clusters of deeply perfumed flowers at this time of year. The blossoms frequently appear in bridal bouquets, and their intense scent is enough to stop curious shoppers in their tracks.
I frequently see people studying these plants, seeming to wonder what they are and how to keep them in bloom. There are some secrets to growing this frost-tender tropical vine that originated in the woodlands of Africa, Madagascar and Asia. Given that this is the beginning of a northern winter, could it be any further out of its comfort zone?
Stephanotis is frequently sold in juvenile form, with its green stems and thick, shiny foliage tightly wrapped around a circular wire frame and stuck into a six-inch (15-cm) pot. The scented blooms are produced in short-stalked axillary cymes, their pristine white waxy petals forming tubular flowers with five spreading lobes. Usually, it’s available in late autumn, with several bunches of the deeply perfumed flowers on display. They may hold on to the stems through December, but then fall off and are seldom replaced with new flushes. Fertilizer fails to provoke any further flower buds, and eventually we grow bored and pitch the plant out. This is a great shame, because a young stephanotis vine is poised to provide a long season of flowers, if we would only pay attention to its blooming cycle.
A summer-blooming plant, stephanotis makes vine growth and repeated flower flushes beginning in spring, and continuing through autumn. Unfortunately, we encounter it as a December holiday plant, just at the end of its long season of bloom. When the last blooms are finished, the plant takes a winter rest period before resuming growth in mid-spring. Understanding the plant’s potential, it’s wise to enjoy the flowers until they drop, and then treat this plant to a restful winter in preparation for a return to flowering in spring and summer.
If we consider stephanotis as a permanent plant, it opens some interesting possibilities for indoor and outdoor gardeners. Outdoors in the tropics, the vine is capable of forming woody stems and growing to 20 feet (6 m), enough to cover a small garage! But it won’t tolerate temperatures lower than 15°C or cold drafts, and in our northern climate stephanotis makes a better permanent container plant.
Although it flowers well when slightly root bound, a new young plant should be potted up to an eight-inch (20-cm) pot. A clay- or loam-based potting soil is preferable to light soilless mix, and the vine should be grown somewhat dry over the winter, providing water sparingly only when the soil is dry. Stephanotis performs best in a humid environment, and in spring and summer, an indoor pot can be set on a tray of pebbles and water, with the water level just below the bottom of the pot. It also appreciates a morning misting when in active growth.
As a permanent plant, we can expect to see new growth in the spring. The wire hoop frame will soon be too small, and it makes sense to get the plant separated from the hoop in the first winter. A new climbing frame will be necessary, and that could be as simple as bamboo stakes with soft ties or a trellis in the pot. An older plant may eventually require pruning to reduce its size, and that can be done in late winter before new growth starts, cutting back main branches by no more than half their length.
Stephanotis can remain indoors permanently, in a sunny window with east or south exposure. It can also be taken outdoors to a patio or apartment terrace for the summer when night temperatures are reliably above 18°C, placing it in bright shade or half a day of sun. During the spring and summer months, the vine will need consistently moist soil and good drainage. Feed every third week with a water-soluble fertilizer with a higher middle number to encourage consistent flowering.
Feel free to pass this information on to those confused supermarket shoppers dallying over the stephanotis pots. With an understanding of this plant’s bloom cycle, we could all enjoy an extravagantly blooming perfumed vine for many summers to come.