How to grow wisteria

Choosing a Wisteria

Wisterias do best in well-drained, fertile soil, in full sun. They are native to China, Japan and eastern United States and, of the ten species, the three most commonly grown are Wisteria floribunda (Japanese wisteria), Wisteria sinensis (Chinese wisteria) and Wisteria brachybotrys (silky wisteria). All three species are strong-growing and capable of reaching around 10m (33ft) in trees or spread up to 20m (66ft) against a wall. You can also train wisteria as a free-standing standard in the border or large container.

Wisterias for pergolas and arches

Japanese wisteria (Wisteria floribunda) have the longest flower sprays (or racemes) of all the species and are best displayed hanging down from a garden structure like a pergola or arch. They twine clockwise and bears flowers and leaves at the same time. Wisteria floribunda f. multijuga AGM, has lilac blue flowers and racemes up to 1.2m (4ft) long in early summer.

Wisterias for walls

Chinese wisteria (Wisteria sinensis) flowers before the leaves appear, making a spectacular display in spring. They twines anticlockwise and the racemes are shorter so best displayed against a wall; for example Wisteria sinensis 'Amethyst' AGM has violet blue flowers with a reddish flush produced in dense racemes to 30cm (1ft) long in late spring or early summer.

Silky wisteria (Wisteria brachybotrys) has downy leaves and short racemes of 10-15cm (4-6in) and can be grown against walls or on pergolas. Wisteria brachybotrys f. albiflora 'Shiro-kapitan' AGM has white flowers with central yellow markings, is highly scented, and hangs in sprays 10-15cm long in spring and early summer.

If you’d like to grow a wisteria in a large container Wisteria fructens ‘Amethyst Falls’  has a compact habit with dense clusters of lilac-blue flowers which makes it ideal. 

When buying a wisteria, always choose one that has been grown from cuttings or by grafting, as seed raised wisterias flower less reliably and also take longer to come into bloom. You should be able to see the graft union as a bulge near the base of the stem. Named cultivars are almost always grafted whereas species are not. To avoid disappointment, buy your wisteria in flower or choose a named cultivar.

Wisterias are sold as container-grown plants in garden centres and online and, to source specific cultivars, you can use the RHS Find a Plant tool.

Planting of wisteria is best done between October and April. Container grown wisterias can be planted at any time of the year, but are easier to care for in autumn or winter. Plant them in fertile, well-drained soil.

Wisterias flower best in full sun so choose a south- or west-facing wall or pergola. They will grow in slight shade but flowering will be reduced.

Wisterias are hardy, vigorous climbers reaching over 10m (33ft) height and width. You will need to provide support in the form of wires or trellis against a wall, or garden structures like pergola or arch. Wisteria can also be trained up a tree or grown up a support to form a standard. By training a wisteria into a standard it restricts its vigour and allows to you to grow a wisteria in a border or container.

If you’d like to grow your wisteria in a container, you’ll need a large container of at least 45cm (18in) filled with loam-based potting compost such as John Innes No. 3.

Watering

Plants will dry out quickly on light or sandy soil so keep them well watered, particularly when newly planted and in dry periods.

Feeding

Feed your wisteria in spring with Growmore or Fish, Blood and Bone at the recommended rate shown on the packet. In sandy soils (which have low potassium levels) also apply sulphate of potash at 20g per sq m (1/2 oz per sq yd). You can also use rose or flowering shrub fertilisers.

In containers, feed wisteria with liquid tomato fertiliser, Phostrogen, Miracle-Gro or a similar flowering plant food. Alternatively you can mix controlled-release fertiliser into the compost.

Wisteria has a reputation for being difficult to prune but this isn’t the case. Once you have established  the routine of pruning your wisteria twice a year, you should be rewarded with a good display of flowers.

Regular pruning means shortening the excessive whippy growth in July/August to five to six leaves, about 30cm (1ft). This allows the wood to ripen and improves the chances of flower buds forming. Then, in February, further shorten these shoots to two to three buds, about 10cm (4in), to tidy the plant before the growing season begins to allow the new flowers to be seen.

Leave your young wisteria unpruned until it has covered the wall or garden structure and then begin the regular pruning to encourage flowering.

Wisteria can be trained as a free-standing standard in a border or container and this is particularly useful for small gardens.

Wisteria can be trained to grow up into the canopy of a small tree, but this may damage the tree over time. If grown into a large tree, pruning will be difficult and the flowering will be effected if the leaf canopy is dense.

Seed-raised wisteria can take up to 20 years to flower, so increase your wisteria stocks by layering in summer, taking softwood cuttings in spring to mid-summer or hardwood cuttings in winter.

Professional nurserymen generally propagate wisteria by grafting, but layering is the easiest and most reliable method for the home gardener.

After a long summer, established wisteria can form pendant, bean-like seedpods. While seed-raised wisteria plants are usually of poor quality you might like to try and grow your own wisteria.

• Collect the seedpods after leaf fall and allow them to ripen in an open tray
• Once ripe, break open the pod by twisting and sow the fresh seed 2cm (¾in) deep in seed compost
• If the seed is dry, soak for 24 hours before sowing

For an overview of wisteria problems see our page on frequently asked questions.

Poor flowering

The most common problem for home gardeners is poor flowering and this can be caused by a number of things including:

• Young plants can take up to 20 years to flower so avoid disappointment by buying a plant in flower or choosing a named cultivar as they are usually grafted
• Check your pruning technique and timing as pruning in early and midsummer will disrupt the formation of flowers for the following year
• Wisteria flowers best in full sun, with few if any flowers forming in deep shade
• Water your wisteria during dry spells between July to September as a shortage of water at this time will affect flower bud formation for the following year
• Spring frosts can damage or distort developing flowers and cause the buds to drop before they open
• Poor soils may be short of potassium, so apply sulphate of potash in spring to promote flower formation for the following year
• Shredded flowers or tell-tale teeth marks are signs of damage by pigeons or mice

Other problems

Sometimes a mature, seemingly healthy wisteria will die and be replaced by a healthy new shoot growing from ground level. This can be caused by wisteria graft failure.

A less common cause of failure is fungal root disease caused by either honey fungus or phytophthora root rot, and wisteria is susceptible to both of these diseases.

Irregular brown blotches and marks on the leaves, usually with a yellow margin, may be a symptom of infection by the fungal disease powdery mildew and wisteria may also be affected by viruses.

Wisterias are also prone to scale infestation and less commonly to wisteria scale.