Wisteria

Wisterias have universal appeal, embellishing elegant townhouses and thatched country cottages with equal aplomb.

Bursting into bloom before the lime-green, pinnate foliage emerges, smothering and covering facades with a wash of dangling, fragrant, lilac tresses, its springtime floral
display is unparalleled.

Wisteria Tree

At up to ten meters tall and five meters across, a single plant can engulf an entire property and deservedly capture the limelight.

The Instagrammers clamor shares sensational, flower-infused images – #wisteriahysteria – and London even has seasonal wisteria walks.

Wisteria transforms the ordinary into the extraordinary, highlighting beauty or concealing eyesores.

These coveted climbers have become almost a status symbol in the city, quintessentially English in the country.

A London property with virtually no garden can put on an astonishing flower show; its entire facade smothered in masses of elegant blooms for weeks on end.

Wisteria’s perfume drifts freely through open doors and windows and attracts throngs of pollinators.

Wisteria Varieties

Wisterias are hardy and long-lived. Britain’s first wisteria, Wisteria Sinensis, arrived from
China in 1816 and still thrives in Kew’s Royal Botanic Gardens – so plant your wisteria wisely.

Chinese Wisteria Sinensis and Japanese native W. floribunda are the two most popular species. They flower in mid-to-late April, May, or June, are lilac in color and are heavily
perfumed.

Generally, Chinese wisteria, W. Sinensis, climbs in a clockwise direction and bears
plump, shortish 25-30cm, lilac flower panicles that bloom just before the foliage emerges.

The most widespread, infallible, Chinese wisteria in cultivation is the very vigorous and floriferous W. Sinensis ‘Prolific,’ holder of an Award of Garden Merit (AGM).

“It’s one of the very best for flowers,” remarks Chris. It blooms early in its life and at the beginning of the season, from mid to late April.

Its vibrant, red flushed violet-blue cousin, W. Sinensis ‘Amethyst’ (AGM), is equally reliable. Both are heavily scented and excellent for clothing the house’s facade, sending up trees, shrouding pergolas, or running along walls and fences.

Japanese wisteria, W. floribunda, spiral in the opposite direction, anti-clockwise, and produce their cascades of long, elegant, pendulous floral racemes, some a meter
long, at the same time as their foliage appears.

These are best enjoyed cascading from arbors, tunnels, archways, and pergolas. Japan’s annual Wisteria Festival, Fuji Matsuri, showcases tunnels dripping with a pastel rainbow of perfumed racemes in every shade of lavender, pink and white.

Wisteria floribunda f. Rosea ‘Hon-beni’ (AGM) is the rosiest of all pinks, bearing 50-60cm long tresses with unrivaled perfume.

‘Hon-beni’ can be trained as a standard and is renowned for flowering early in its life, but later in the season, from mid-May.

W. floribunda f. alba ‘Shiro-noda’ produces showy, 60cm-long, white blooms, while double-flowered W. floribunda ‘Yae-kokuryu’ (often offered for sale as Wisteria ‘Black Dragon’) has darker, indigo-black blooms.

The most vigorous and enchanting of all floribundas is award-winning, long-flowering Wisteria floribunda f. multijuga (AGM), which has exceptional, meter-long, densely
clustered, lilac, and purple blooms.

An earlier-flowering Japanese species, silky wisteria or W. brachybotrys, is noteworthy for its immense vigor.

Its climbing ability exceeds that of all other wisterias: it can scramble beyond 12
meters and spread at least eight.

The versatile white cultivar W. brachybotrys f. albiflora ‘Shiro-Kapitan (AGM) can scale great heights and make a good container plant for the small garden.

Purple species Wisteria brachybotrys and the outstanding cultivar ‘Okayama’ are very similar and favored by many for vibrancy and unparalleled vigor.

AGM holder ‘Okayama’ bears masses of fragrant but much shorter blooms that are 15cm
long, amid dark bronze foliage.

How Fast Does Wisteria Grow

Wisteria are versatile, hardy, relatively quick growing, and prolific if you follow a few essential rules.

Buy a five- to seven-year-old grafted plant since younger plants rarely flower and plant when dormant (October-March) in a sunny, sheltered south- or south-west-facing position.

The foot of a wall is ideal as it will protect flower buds against late frosts. Plant in rich, moist but free-draining soil, leaving plenty of room for root growth. Poor drainage can inhibit flowers.

Wisteria also needs to be given a robust climbing frame: a sturdy wooden or metal arbor, pergola, or stout trellis to train the vine.

Horizontal wires fastened to strong, metal, wall-fixed vine eyes will provide optimum support for well-trained wisteria. Loosely tie-in lead shoots, leaving ample room for growth of girth.

Fertilize the soil annually in March with potash- and magnesium-rich rose feed to help promote abundant blooms, but bi-annual pruning is key to keeping your wisteria
under control and maximizing its flowering potential.

SUMMER PRUNING

When does wisteria bloom? After flowering, in July or August, shorten the current year’s growth – all those long, unruly, and unnecessary shoots – to five-to-six leaves, or around 15cm.

This encourages flower-bud production over leaves and exposes the stubbier, woody side arms to full sun to encourage more blooms next year.

WISTERIA PRUNING Step by step

Wisteria are pruned twice: first in winter (shown here) followed by a summer prune.

Do this every year, and spectacular floral displays will follow.

Before Winter, pruning is done in January to February before the flower buds emerge. The idea is to prune hardback to encourage flowering spurs, remove dead wood and weak branches. You’ll need sharp, clean loppers or secateurs and a steady ladder.

Step 1 Tidy up and maintain the wisteria’s framework. Remove congested stems, dead wood, old foliage, and long whips to focus the plant’s energy on producing flowering spurs, not vegetative growth. Leave any stems required to extend the framework.

Step 2 Tidy up flower spurs, removing dead twigs and foliage stems to create a clear, open habit for flower production.

Step 3 Remove congested stems, leaving upright flowering spurs at regular intervals of around 30-40cm.

Step 4 Shorten the remaining flower spurs back to two or three buds by making a sharp upward cut above but not close enough to damage the selected remaining buds. This tidies the vine and allows sunlight to reach the flower buds.

Step 5 Loosely tie in any whippy shoots or stems with wire or twine to extend your framework upwards or outwards. Then remove all debris (Mark uses a leaf blower).

The result should be a framework of well-spaced branches with stumpy spurs.