Cup-and-Saucer Vine, Cobaea scandens
“An interesting and unusual plant which should find a place is Cobaea scandens, which sounds more attractive under its English name of cups-and-saucers,” wrote the virtuoso English gardener Vita Sackville-West, who grew the vine in her Sissinghurst Castle garden.
When Vita Sackville-West recommends a plant, I listen. This perennial climbing vine has flowers shaped like tea cups (which “sit” in more petals shaped like saucers) is a warm-weather plant that hails, originally from Mexico. In colder climates, consider it an annual but don’t worry—it can easily 10 feet in a single season.
Is cup-and-saucer vine a good choice for your garden? Read on to learn more:
Above: Cup-and-saucer vine blooms in Maui in December. Photograph by Forest and Kim Starr via Flickr.
Flowers change color as they bloom. When they open, cup-and-saucer flowers are “a creamy white; then they turn apple-green, then they develop a slight mauve blush, and end up a deep purple,” wrote Sackville-West.
Except for the ones that don’t. C. scandens ‘Alba’ is a white-flowering cultivar.
Above: A packet of 15 Cup and Saucer ‘Alba’ seeds is $3.95 from Floret Flowers.
“The ideal place for it is a trellis nailed against a wall, or a position at the foot of a hedge, when people will be much puzzled as to what kind of a hedge this can be, bearing such curious short-stemmed flowers, like a Canterbury bell with tendrils,” she wrote.
Above: Photograph byMichael Wolfvia Wikimedia Commons.
Before you plant cup-and-saucer vine, do some research. C. scandens can become invasive in some regions (and by the way is not welcome in New Zealand). In that habit, it resembles another purple climbing vine, morning glory.
Above: Photograph via @Bisselingskaat.
- Grow cup-and-saucer vine as a cloak on an ugly chain link fence, or on a trellis to frame a doorway.
- Start training a vine when it is young and malleable. Wherever you pinch off a stem, expect lateral offshoots.
- Plants with grassy textures make good visual companions for cup-and-saucer vine. Ground covers such as lilyturf (Liriope) and feathery ornamental grasses such as graceful maiden grass (Miscanthus) are good choices.
Above: Seeds are for sale via Njuškalo.
Keep It Alive
- A warm-weather plant, C. scandens is winter-hardy only in USDA growing zones 9 to 11.
- Plant cup-and-saucer vine in full sun, in a site with well-drained soil.
- Easy to start from seed, cup-and-saucer vines can be started indoors and transplanted to the garden after the last frost date.
See more growing tips in Cup-and-Saucer Vine: A Field Guide to Planting, Care & Design in our curated guides to Vines & Climbers 101. Read more about how to use flowering vines in a landscape:
- 9 Ways to Create Curb Appeal with Flowering Vines and Climbers
- Passionflower: A Field Guide to Planting, Care & Design
- Everything You Need to Know About Houseplant Vines
Cathedral Bells (Cobaea)
Characteristics and Pruning
Cobaea scandens originates from Mexico and Costa Rica and was introduced in Europe in 1789 (Botanical Garden Madrid) before quickly spreading. An annual in Europe, it develops tiny, branched tendrils similar at the ends of the feathered leaves that quickly cling to irregularities, much like the leaf-stem tendrils (petiole climbers). On rough surfaces it might even be self-climbing. Planting is done in the middle or end of May with a planting distance of 45 – 60 cm, with optimal soil even up to 1.5 m. Cathedral bells can grow up to 8 metres in height. Flowers are greenish first, then turn white and purple or violet. Flowering time is July to October. There is a white-flowering cathedral bell– “Albiflora” — with lighter leaves. “Variegata” blooms purple, but has white leaf edges. Cutting the tips of the shoots promotes branching and the number of flowers. Flowering time is July to October. For seed breeding/cultivation: pollinate the first flowers of the year with a brush after nightfall and re-fertilise and/or pollinate them at the stage of the outgoing flower (when the flowers begin to tilt downwards/point to the ground).
How to grow: Cobaea scandens
These flowers are on longish stalks that hold them out in front of the leaves. There is also a white form (actually a very pale creamy-green) called ‘Alba’, which is harder to find and not quite so showy. The flowers, once they have developed, give off a very pleasant scent (they are pollinated in Mexico by bats). The leaves are 4in long, composed of four leaflets and a tendril with many little hooks on it, which it uses to climb; Charles Darwin was so impressed he studied cobaea for his book The Movements and Habits of Climbing Plants (1875).
Cobaea scandens will appeal to anyone who longs for something with panache and visual impact. It will also solve the problem, temporarily at least, of what to do with a bare wall space if something unexpectedly dies.
Cobaea scandens should be sown in late winter or very early spring, individually in small pots in seed compost, each seed set on its edge and thinly covered with more compost or perlite. Cover the pots with clingfilm to retain moisture and put in a windowsill propagator. Germination takes three weeks to a month. Once germinated the seedlings should be moved to larger (5in) pots with stakes inserted so that the young stems have something around which to twine. Grow them on at a cooler temperature. Harden them off carefully and put the young plants out in the garden when the danger of frost is past, against a sturdy trellis or close to a south-facing wall or fence on to which wires or netting have been attached. Cobaea does best in moist but well-drained soil, so water regularly in dry spells.
Cobaea scandens can be grown in a large pot (at least in diameter) in large cool greenhouse or conservatory, as long as suitable wires are provided for it to cling to. Any pot-grown cobaea needs copious watering and protection against glasshouse red spider mite. They will overwinter provided that the temperature at night does not dip below 5C.
Cobaea scandens has the capacity to swamp more genteel climbers, such as Clematis viticella cultivars or Rhodochiton volubile, which might look like suitable companions. However, if grown on a trellis or wall it will make a good backcloth to summer perennials growing in the border in front. Aster frikartii ‘Monch’, Echinops bannaticus ‘Taplow Blue’, Strobilanthes atropurpurea and Echinacea purpurea would all associate well, as do annuals like the green-flowered Nicotiana langsdorfii and N. ‘Lime Green’, and pink Cosmos bipinnatus. But this is a plant which can stand alone.
Where to buy
The best way to get hold of Cobaea scandens or C. scandens ‘Alba’ is to order seed from a general seed firm in winter. Chiltern Seeds, and Thompson and Morgan carry both varieties. They are also available in spring from Penpergwm Plants, Penpergwm Lodge, Abergavenny, Gwent (01873 840422; www.penplants.com). No mail order. Catalogue costs 2 x 1st-class stamps. Garden and nursery open 2pm-6pm, Thursday to Sunday, end of March to end of September.
There is a seemingly unsolvable conundrum for the many gardeners among us who would like vertical interest and colour in summer without having to wait a year or two for shrubs or perennial climbers to develop sufficiently to flower well.
The simple answer is to sow the seed of annual climbers, which have the capacity to germinate, grow stupendously, flower generously and set seed within a few short months. They can be so imposing that they often transform the look of a garden – all for surprisingly little bother.
Annual climbers are, in fact, often perennials that are too tender to survive frost in winter; a favourite of many gardeners is the beautiful and fast-growing Cobaea scandens.
Cobaea scandens is an impressive climber and is one of the fastest-growing and most trouble-free vines you will ever grow. In its native Mexico it makes a woody, evergreen perennial. Here it grows 10ft or so over the summer and, from summer until the first frosts, produces very large and distinctive flowers that begin a greenish-white but turn to an inky purple with age.
The bell-shaped flowers are up to 5cm (2in) in diameter and have a ruff of bracts – hence its common names, cup and saucer plant or cathedral bells. The flowers are on longish stalks that hold them out in front of the leaves.
It will behave as a perennial if kept indoors in winter at about 7°C (45°F). In a very mild winter plants may survive and remain virtually evergreen,
Cobaea scandens will appeal to anyone who longs for something with panache and visual impact. It is extremely attractive when scrambling upward through trellis work, archways, over small buildings or old trees. It will also solve the problem, temporarily at least, of what to do with that bare wall and will fill the air with a very pleasant honey scent throughout the growing season.
- Cobaea scandens has been awarded the prestigious RHS Award of Garden Merit (AGM).
Sowing: Sow indoors in January to March or sow in September to overwinter in a coldframe
They will flower 20 weeks from sowing and if grown in a greenhouse will flower for 8 months of the year.
Soak the seed for two hours in lukewarm water before sowing. Sow the seeds into individual small pots containing good quality seed compost. Sow 12mm (½in) deep, setting the large flat seeds on edge and sticking vertically into the soil, thinly cover with compost or perlite. Cover the pots with plastic or cling film to retain moisture and place on a windowsill or into a propagator.
The minimum temperature for germination is 16°C (60°F) the ideal temperature is around 21°C (70°F). Make sure the compost is kept moist but not wet, watering from the base of the pot. Germination usually takes three weeks to four weeks.
Once germinated the seedlings should be moved to larger 12cm (5in) pots with stakes inserted so that the young stems have something around which to twine. Grow them on at a cooler temperature.
For conservatory or greenhouse plants pot on as the plants develop. For outdoor plants harden them off carefully and put the young plants out in the garden when the danger of frost is past
Grow the plants against a sturdy trellis or close to a south-facing wall or fence on to which wires, netting or a frame has been attached. Plant 45cm (18in). apart. Cobaea does best in moist but well-drained soil, so water regularly in dry spells.
The plants can be grown in a large pot (at least in diameter) in large cool greenhouse or conservatory, as long as suitable wires are provided for it to cling to. Any pot-grown Cobaea needs copious watering and protection against glasshouse red spider mite.
Cobaea scandens is in fact, a perennials that is too tender to survive the frosts in winter. In the greenhouse they will overwinter provided that the temperature at night does not dip below 7°C (45°F).
Excellent for clambering up trellises, pagodas, walls and fences.
A native of tropical America including Mexico.
Cobaea scandens is pollinated by bats and at dusk – at about the time that bats would emerge – the flowers emit a scent that attracts them. The bats visit for nectar but as they probe the flower those protruding stamens dust their furry chests with pollen that they transport from plant to plant.
Charles Darwin was so impressed he studied Cobaea for his book The Movements and Habits of Climbing Plants (1875).
The genus Cobaea is named after Bernabé Cobo (1582-1657), a Jesuit missionary and naturalist.
Bernabé Cobo lived 61 years in Mexico and South America and much of what we know about the Inca civilization is all due to the writing of this one remarkable Spanish priest.
Arriving in Peru in 1599, he visited the former Inca capital, Cuzco, in 1609 and spent the rest of his life writing a 47 volume “History of the New World,” which he completed in 1653. Cobo recorded much of the information we know about the Inca 100 years after the Spanish conquest; some of these are still in press after some four hundred or more years.
Father Cobo was beyond all doubt the ablest and most thorough student of nature and man in Spanish America during the seventeenth century. Yet, the first, and almost only, acknowledgement of his worth dates from the fourth year of the nineteenth century.
The distinguished Spanish botanist Cavanilles not only paid a handsome tribute of respect to the memory of Father Cobo in an address delivered at the Royal Botanical Gardens of Madrid, in 1804, but he gave the name of Cobæa to a genus of plants belonging to the Polemoniaceae family of Mexico, Cobæa scandens being its most striking representative.
The species name scandens simply means ‘climbing’.
The bell-shaped flowers have a ruff of bracts, hence the common names, Cup and Saucer Vine, Cathedral Bells or Monastery Bells
Cobaea scandens alba, the Cathedral Bells or Cup and Saucer Vine, is a perennial vine from Central and South America. It’s completely carefree, and will grow 15-25 feet in one season. It’s a showy climber for the cool greenhouse, and also forming a very decorative screen on trellis or south facing wall in milder areas. The vine can reach 20 feet in length or higher and produces numerous large flowers, often 6 cm (2½ in) across. Beautiful climber with truly bell-like yellowish-white flowers. The buds mature from late Summer to early-mid Fall. A profuse bloomer. The fruit capsule is 5.5 to 8.5 cm long, with broad seeds 10-15 mm long including the wing. Cobaea scandens is a fast-growing, evergreen perennial climber with tendrils on its leaves. The leaf of Cobaea is compound and consists of leaflets, stipules, and tendrils. Each leaflet is oval, 4-12 cm long by 2-5 cm wide, dark green above, whitish underneath, with a brown stalk. The vines have many tendrils and cling well to rough surfaces. Hardiness zones 9-11, (-5°C/25°F, 4°C/40°F) in Winter. Annual elsewhere. Provide a sunny growing area with a light, rich soil. Water regularly; do not overwater the soil should be moist to wet.
Native to Mexico. Extremely vigorous growth to 25 feet in a single season. Bell-shaped, summer-to-fall owers are rst greenish, then violet or rose purple. The common name describes the flower form: a 2 inches-long cup of petals sits in large, saucerlike green calyx. Leaves are divided into two or three pairs of oval, 4 inches leaets; a curling tendril at the end of each leaf enables the vine to climb rough surfaces without support. ‘Alba’ has white blooms. ‘Key Lime’ has pale green flowers. Blossoms of ‘Royal Plum’ emerge light green, then mature to rich deep purple with a white- streaked throat and chartreuse anthers.
Blooms rst year from seed. In the Tropical South and milder parts of the Coastal South, the vine lives from year to year, eventually reaching more than 40 feet in length and blooming heavily from spring to fall.
The hard-coated seeds may rot if sown outdoors in cool weather. Start indoors in 4 inches pots; notch seeds with a knife and press them edgewise into moistened potting mix, barely covering them. Keep moist but not wet; transplant to warm, sunny location when weather warms up. Protect from wind.