(Species: Wisteria - Family: Leguminosae/Papilionaceae)
Wisteria and its origins
Wisteria is a group of hardy deciduous, woody-stemmed, twining climbers that are native to East Asia and North America. They are loved universally for their spectacular flower cascades that are frequently grown on the front of a house wall.
The English botanist Thomas Nuttall, who lived in America in the early 19th century, named wisteria after Caspar Wistar, the American professor of anatomy, which is why the common name for wisteria is sometimes spelt 'wistaria'. It was originally known as glycinia, after the Greek word for sweet, 'glykys'.
Seasonality: Wisteria in flower
Wisteria flowers in late spring and early summer, producing hanging racemes of pea-like flowers on its twining stems. The flowers are typically lilac in colour, but can range in shades from pure white and soft pink to deep mauve and have a scent redolent of pepper and vanilla. The racemes are usually about 25cm in length but on W floribunda Multijuga they can be 1metre or more. The pinnate leaves, velvety seed pods and mature gnarled trunks are other attractive features of the wisteria.
A wisteria needs to be chosen with care: Chinese wisteria, W sinsensis, which often has a small second flush of flowers later in summer, can reach 18-30m, while Japanese wisteria W floribunda is less vigorous and has a smaller span of 4m or more.
Always buy a container-grown plant from a reputable garden centre or nursery that has been propagated by an expert rather than grown from seed, because flowering will be quicker by years.
How to plant
The wisteria is only as good as the location it is planted, so choose the location, like the plant, with care. For example, use a house wall, an expansive pergola or even a tall tree as host. The site should have full sun to encourage the best blooms.
Wisteria grows best in moist, fertile and well-drained soil. Chalky soil will benefit from the addition of loamy soil added to the planting hole.
Keep the plant well watered while it is being established, especially during drought.
In the early years of the plant, pruning should be focused in forming a strong framework of primary branches. Large specimens might need an annual hard pruning in late winter to keep them within limits. In summer, prune wisteria by shortening the current year's leafy side growths to five or six buds.
Propagation of Wisteria
Seedlings may not flower for many years and often produce poor flowers; taking wisteria cuttings is a quicker method. In late spring or early summer, take softwood cuttings that have at least two sets of leaves on each cutting.
Remove any sets of leaves on the lower half of the cutting, and trim so that the lowest node is about 1cm from the base of the cutting. Place cuttings around the edge of a small pot filled with well-drained potting compost and place in a propagator in a bright location with indirect light. Keep the soil moist and the cuttings should root in 4-6 weeks.
Did you know?
The world's largest wisteria vine is listed in the Guinness Book of Records. It grows in Sierra Madre, California, and has a festival held in its honour which attracts about 15,000 visitors each spring. The vine weighs over 250 tons, is over one acre in size and produces more than 1.5 million blossoms every year. It was planted in 1894 by William and Alice Brugman who bought the Chinese variety for 75 cents and planted it near their home.