Wisteria floribunda 'Issai-naga'
Japanese wisteria 'Issai-naga'
Large, vigorous, deciduous climber about 9m tall, with twining stems, and green leaves divided into leaflets, that turn butter-yellow in autumn. Drooping racemes to 30cm long, of scented, pea-like, mauvish-blue flowers, marked violet-mauve, produced in late spring, often followed by bean-like velvety, blue-grey seed pods 15cm long. Free-flowering from a young age
Size
Ultimate height
8–12 metresTime to ultimate height
10–20 yearsUltimate spread
Wider than 8 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
Stem | Flower | Foliage | Fruit | |
Spring | Blue Purple | Green | ||
---|---|---|---|---|
Summer | Green | Grey Silver Green | ||
Autumn | Yellow | |||
Winter |
Position
- Full sun
- Partial shade
Aspect
South–facing or West–facing or East–facing
Exposure
Sheltered Hardiness
H6Botanical details
- Family
- Fabaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Climbing
- Potentially harmful
- Harmful if eaten. Wear gloves and other protective equipment when handling. Pets: Harmful if eaten - for further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
- Genus
Wisteria are vigorous woody climbers with twining stems bearing pinnate leaves and long pendulous racemes of fragrant pea-like flowers in spring and early summer
- Name status
Accepted
How to grow
Cultivation
A large, long-lived climber so choosing the right site is important. Can be grown informally through large tree or more formally against a house wall. Will grow in most soils that are moist but well-drained in sun or part shade. See wisteria cultivation for more advice
Propagation
Propagate by layering in spring, softwood cuttings from late spring to early summer, hardwood cuttings in winter, root cuttings in late winter or grafting in late winter
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Climber and wall shrubs
- Wall side borders
Pruning
Prune twice a year for best results, see pruning wisteria for detailed advice
Pests
May be susceptible to aphids, glasshouse red spider mite, and scale insects including wisteria scale
Diseases
May be susceptible to honey fungus (rarely), phytophthora root rot, coral spot, fungal leaf spot, virus diseases, and powdery mildews
Get involved
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