Cobaea scandens f. alba

Also known as cathedral bells, Cobaea scandens is a vigorous vine, native to tropical America, where it grows as a woody perennial. The flowers are typically blue and thrive in the greenhouse or conservatory, but may also be grown as an annual in a sunny border or patio. Given the right conditions indoors, Cobaea scandens can flower all year long. Watch Monty Don's guide on potting this climber.

Cobaea scandens f. alba has clear white flowers. It's a rampant climber, and will quickly scramble up a trellis or obelisk. For best results grow in fertile, well-drained soil in full sun, or in containers on the patio or in the greenhouse or conservatory. If protected from frost in winter, Cobaea scandens f. alba may survive, and could even continue flowering. It makes an excellent cut flower.