Climber
How to grow wisteria
Wisteria sinensis / W. floribunda
Wisteria needs a sunny south or west wall or a strong pergola, deep soil and a permanent set of wires. Plant between October and April, and buy a grafted, named plant, because seedlings can take 15 to 20 years to flower. What makes it flower is pruning twice a year, in July or August and again in January or February, along with potash and very little nitrogen. It flowers in May and June.
- Hardiness
- Fully hardy
- Position
- Full sun, warm wall
- Soil
- Deep, fertile, free-draining
- Ideal pH
- 6.0 to 7.0
- Water
- Moderate; regular in the first two summers and for wall-trained plants
- Feeding
- Moderate feeder
Sowing and planting wisteria
WhenPlant Oct to Apr; prune Jul to Aug and Jan to Feb; flowers May to Jun
Starting off
Plant a pot-grown, grafted, named plant Oct to Apr, as seedlings can take up to 20 years to flower; choose one already in flower in May. Propagate by layering a low shoot in Mar to Apr, rooted in 12 months, or by softwood cuttings 10 cm long in Jun at 20 °C. Seed is not worth sowing.
Spacing and planting
Plant one per wall, 30 cm out from the base with horizontal wires at 30 cm intervals; it reaches 10 m or more. Dig a hole 60 cm wide with compost and plant at pot depth with the graft above soil. A 60 cm pot can hold a standard-trained plant for a few years with daily summer watering.
Varieties worth growing
- W. sinensis 'Prolific'
- Chinese wisteria that flowers from a young age, with scented lilac-blue racemes opening before the leaves in May. The usual choice for a house wall.
- W. floribunda 'Multijuga'
- Japanese wisteria, also sold as 'Macrobotrys', with racemes that can reach a metre long. Best over a pergola or arch where the flowers can hang clear.
- W. floribunda 'Alba'
- White Japanese wisteria with long, scented racemes opening with the leaves, a little later than the Chinese kinds and so less often caught by frost.
- W. brachybotrys 'Shiro-kapitan'
- Silky wisteria: short, broad racemes of large white flowers with the strongest scent of all, on downy foliage. Less rampant than W. sinensis.
- W. frutescens 'Amethyst Falls'
- A compact American wisteria that flowers in June on the current year's growth and repeats lightly. Much less vigorous, so the one for a large pot or a small garden.
Wisteria month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
Winter prune: shorten last summer's cut shoots to 2 or 3 buds. Check wires and ties.
- February
Finish the winter prune before buds swell. Potash feed late in the month. Plant.
- March
Plant. Mulch the root area. Layer a low shoot to make a new plant.
- April
Flower buds swell. Water plants against walls if the spring is dry. Feed young plants only.
- May
Flowering. A late frost can brown buds on exposed walls.
- June
Cut off spent racemes. Tie in the shoots you want to keep as framework. Take softwood cuttings.
- July
Summer prune: cut the whippy green side shoots back to 5 or 6 leaves.
- August
Finish the summer prune. Water in dry weather, when next year's flower buds are forming.
- September
Cut back any long shoots that have regrown since the summer prune.
- October
Plant.
- November
Plant. Once the leaves fall, check the framework and loosen tight ties.
- December
Nothing to do. The winter prune can start in a mild spell.
Feeding wisteria
Wisteria is a legume and makes its own nitrogen, so nitrogen feed gives leaf and no flower. An established plant wants potash once a year in late winter and nothing else. Only young plants and plants in pots get a liquid feed.
Go easy on nitrogen (it gives leaf, not flower) and feed potassium, sulphate of potash in late winter is the classic way to bring on flowering.
Feeding plan
At planting
5 g per litre of root ball, dusted onto the roots: 25 g for a 5 litre pot, 50 g for a 10 litre pot. Once.
Late February, established plants
20 g/m², the bottom of the label range, over the root area and watered in. For a wall plant, treat a strip about 2 m long and 1 m wide: 40 g. Once a year.
Late February, as an alternative to sulphate of potash
Potassium Rich Fertiliser 11% K
150 g/m² of root area, the bottom of the label range for trees and shrubs, once a year: 300 g for the same 2 m² strip. Use one or the other, not both.
April to June, first two years only
3 ml per litre of water once a fortnight: 27 ml in a 9 litre can, one can per plant. Stop once the framework is growing strongly.
Pots, April to August
3 ml per litre of water once a week in place of a plain watering.
Signs to watch
No flowers on a 5-year plant
Seedling-grown, nitrogen-fed or unpruned
Prune twice yearly, stop nitrogen, feed sulphate of potash in Feb
Leaves yellow between the veins on chalk
Lime-induced chlorosis
Sulphur, chelated iron and an acidic mulch
Buds drop in Apr
Dry roots or late frost
Water deeply and mulch
Pests, diseases and problems
The top of the plant dies quite suddenly while strong shoots grow from the base
Graft failure: the join between rootstock and named variety has broken down, and the regrowth is rootstock
Nothing restores the top. Replace the plant, since rootstock shoots are seedling wisteria and may not flower for many years.
Vigorous shoots coming from below the knobbly graft union near soil level
Suckers from the rootstock
Trace each one back and cut or pull it off where it starts, as soon as seen, before it outgrows the grafted variety.
Large, dark brown, limpet-like scales up to 1 cm across on the stems; branches weaken and die back
Wisteria scale, a sap-sucking insect found mainly in London and the south-east
Scrub or scrape scales off small infestations and prune out badly affected stems. Check any new plant before buying.
Leaves wilt and yellow, branches die back, the whole plant declines over a season or two
Root disease: honey fungus, or phytophthora root rot in wet ground
No cure. Remove the plant with as much root as possible and improve drainage before replanting with something else.
Brown blotches or a pale powdery film on leaves in late summer
Leaf spot or powdery mildew
Neither does lasting harm. Rake up fallen leaves, and water in dry spells.
Flower buds pecked out or stripped in early spring
Pigeons and other birds, occasionally mice
Net a small plant from March until the buds lengthen. On a large plant the losses are usually too few to matter.
Pruning
Pruning and care
Two prunes a year: in Jul to Aug cut this year's whippy side shoots back to 5 to 6 leaves (30 cm); in Jan to Feb shorten the same shoots to 2 to 3 buds (10 cm) to build flowering spurs. Tie the leaders horizontally along wires over 3 to 4 years. Deadhead spent racemes in Jun to stop seed pods forming. Fully hardy; a May frost can brown buds on an exposed wall.
Good to knowTwo prunes a year (summer and winter) control it and build flowering spurs; be patient, grafted plants flower soonest.
Growing wisteria in pots
Wisteria can be kept in a pot only as a trained standard, and only with commitment. Use a container at least 45 cm wide to begin with, moving up to 60 cm, with loam-based compost and a stout stake to hold the single stem. Prune twice a year exactly as for a wall plant to keep a tight head of spurs. Water daily from May to September, since a dry spell in July or August costs next year's flowers. W. frutescens 'Amethyst Falls' is the most manageable choice. Repot or replace the top 5 cm of compost each March.
Wisteria: common questions
Why is my wisteria not flowering?
The three common causes are a seed-raised plant, no regular pruning, and too much nitrogen. Seedlings can take 15 to 20 years to flower, so check for a graft union near the base. Prune every July or August and again in January or February to build flowering spurs, feed potash only, and keep the plant watered in late summer when buds form.
When do you prune wisteria in the UK?
Twice a year. In July or August, cut the long whippy shoots of the current year back to five or six leaves. In January or February, shorten those same shoots again to two or three buds. Shoots needed to extend the framework are tied in and left unpruned.
Will wisteria damage my house?
Not if it is trained and pruned. Wisteria twines and does not cling, so it needs wires and will not harm sound brickwork. The risk comes from unpruned stems forcing their way behind gutters, downpipes and under roof tiles, where they thicken and lever things apart. Keep growth below the eaves and off pipes.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.