Wisteria japonica

Wisteria japonica
Light:
Moisture:
Hardiness:	8
Soil pH:	5.6-7.3
Blooms:	Mid Summer-Late Summer
Open Woods Forest
Native to:	Asia
Nitrogen Fixer
Edible Rating:
Tea:	Yes

Wisteria japonica

Propagation: The seed does not exhibit any dormancy habits. It can be sown as soon as it is ripe in a cold frame and should germinate in the spring. Pre-soak stored seed for 24 hours in warm water and then sow in a greenhouse in early spring. The seed can also be sown in an outdoor seedbed in late spring. Germination should take place in the first spring, though it can sometimes be delayed for another 12 months. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in a cold frame for their first winter. Plant them out in late spring or early summer. Plants are very slow from seed and can take up to 20 years to come into flower.

Basal cuttings of side-shoots in early to mid summer in a frame. Take the cuttings as soon as the new growth has hardened sufficiently, each cutting should have 2 - 3 leaves. It can also help to remove a shallow slice of bark from the bottom 15mm of the cutting to expose extra cambium, since this will encourage more callusing and better rooting. When kept in a mist frame with a bottom heat of 27 - 30°c, they will root within 4 weeks and produce well-established plants by the autumn.

Layering in spring. Simply lay any convenient long shoot along the ground and cover it with a shallow layer of soil. The shoot will readily produce roots at intervals along the stem. When these are well formed, the shoot can be divided up into a number of plants. These should be potted up and kept in a lightly shaded position in a greenhouse until well established and can then be planted out as required.

Cultivation: Prefers a good loamy soil in a sunny south or south-west facing position, sheltered from cold winds and from early morning sun on frosty mornings. Plants can become chlorotic on alkaline soils. A soil that is too rich results in excessive foliage at the expense of flowering.

This species is not hardy in the colder areas of the country.

There is some confusion over the correct name of this species, many authorities referring it to a separate genus as Millettia japonica (Sieb.&Zucc.)A.Gray..

Plants can take a few years to settle down after planting out. Too much shade or too rich a soil are normally the culprits, some form of root restriction can be beneficial.

A climbing plant, attaching itself to branches or whatever by twining in a clockwise direction.

Plants in this genus are notably susceptible to honey fungus.

This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. The plants also form a symbiotic relationship with a mycorrhizal fungus which makes more water, phosphorus and other minerals available to the plants.

Range: E. Asia - Japan, Korea.

Habitat: Clambering over cliffs and trees on woodland edges and in thickets in lowland, C. and S. Japan.

Edibility: Seed - cooked. A famine food, used when all else fails. Some caution is advised, see the notes on toxicity at the top of the page.

Young leaves - cooked. A famine food, they are only used when all else fails.

Pollinators: Insects

Soil: Can grow in light, medium, and heavy soils.

Drainage: Prefers well drained soil.

Flower Type: Hermaphrodite

Known Hazards: The seed of all members of this genus is poisonous.

Also Known As: Milletia japonica. Sieb.&Zucc.

Links

• Wisteria japonica - Plants for a Future