Our guide to growing and caring for wisteria
Wisterias are gorgeous climbing plants, perfect for covering walls and fences or grown over pergolas and arches where their flowers can be appreciated cascading overhead.
When does wisteria bloom? In May and June (sometimes with a smaller second flush later in the summer), producing delightfully scented flowers in shades of purple, white or pink.
How to grow Wisteria
Cultivation
Wisterias need a sunny, sheltered position to flower well. They can be grown in very lightly shaded positions, but won’t flower as well.
They also need a soil that retains plenty of moisture in summer, but doesn’t become overly wet or waterlogged. If grown up against walls, the soil can become very dry, as can light, sandy soils, so may need watering during prolonged, dry periods – and certainly while plants are establishing. Give the soil a 7.5-10cm (3-4in) thick mulch to conserve soil moisture.
When to feed wisteria in the UK
The best time to feed wisteria in the UK is in early spring, mainly in March, as this gives the plant plenty of nutrients at an early stage to promote strong growth and healthy flowering.
Types of wisteria
There are two main species of wisteria commonly grown in gardens:
- Wisteria sinensis is vigorous and only really suitable for covering large areas. It produces its flowers before the leaves appear.
- Wisteria floribunda is more compact and more suited to growing in smaller areas. It produces its flowers and leaves at more-or-less the same time.
Interestingly, the stems of Wisteria sinensis twine anticlockwise, whereas those of Wisteria floribunda grow clockwise – useful to know if you want to distinguish between the two.
Suggested planting locations and garden types
Walls and fences, pergolas and arches, patios, containers, city and courtyard gardens, cottage and informal gardens.
How to care for wisteria
Feeding wisteria plants every spring will give the best results. You can use Miracle-Gro Growmore Garden Plant Food or Miracle-Gro® Fish, Blood & Bone All Purpose Plant Food, but a rose or flowering shrub feed will generally give better results. In very well-drained soil, also feed with sulphate of potash in summer.
Pruning wisteria
Wisterias don’t need pruning – but they can grow out of control and and the flowers hidden by the foliage, and they will flower much more profusely if you do. The aim is to build up lots of short flowering spurs.
Initially, it is more important to train the plants to produce a main framework of main branches, and tie them in to their support to ensure they fully cover the support evenly, than worry too much about flowering.
Once the framework has been produced, you can start pruning for flowers – which needs to be done twice a year. In summer (July or August) shorten the current year’s shoots to around 30cm (12in) long, or 5-7 leaflets from the main stem/framework. Then in winter (December - February) cut back the shoots that were pruned in summer to around 2.5-5cm (1-2in) or a couple of buds.
How long does wisteria flower for?
Typically, it will bloom for several weeks, taking into account the extra bloom that often occurs towards the end of the summer. Wisteria generally blooms later in the spring, most often in May but sometimes in early June, depending on how warm and growth-friendly the spring weather has been.
Poor plant health isn’t the only reason why some wisterias don’t bloom. Youth is also a factor: some plants won’t flower until they are several years old. To maximise your chances of your plant flowering, ensure it’s fed with a fertiliser rich in phosphorus, deadhead any spent blooms to promote new growth, and prune twice a year (once at the start of the year, and again in midsummer).
Pests
Wisteria may be susceptible to the following pests, diseases and problems: Birds, frost damage and graft failure.
| Flowering season(s) | Spring, Summer |
|---|---|
| Foliage season(s) | Spring, Summer, Autumn |
| Sunlight | Full sun |
| Soil type | Chalky, Loamy, Sandy |
| Soil pH | Alkaline |
| Soil moisture | Moist but well-drained |
| Ultimate height | Up to 10m (33ft) |
| Ultimate spread | Up to 10m (33ft) |
| Time to ultimate height | 10-15 years |
