Siberian pea-tree (Caragana boisii)
At a glance
- Lifecycle
- Perennial (hardy)
- Exposure
- Full sun
- Frost limit
- −45.6 °C
Cultivation
Succeeds in most well-drained soils, preferring full sun and a light sandy dry or well-drained soil. This species is hardy to at least -30°c. This species is closely related to C. arborescens, differing in the longer teeth of the calyx and in the downy ovary and young fruit. It can probably be used in all the ways C. arborescens is used and therefore has an excellent potential for human food.[K]. A good bee plant. Plants in this genus are notably resistant 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.
Propagation
Seed - best sown as soon as it is ripe in a cold frame. As soon as they are large enough to handle, prick the seedlings out into individual pots and grow them on in a greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Cuttings of half-ripe wood, 7 - 10cm with a heel, July/August in a frame. Layering in spring.
Edible uses
The following uses are for the closely related C. arborescens and can probably also be applied to this species[K]. Seed - cooked. Young pods - cooked and used as a vegetable.
Material uses
The following uses are for the closely related C. arborescens and can probably also be applied to this species[K]. A fibre is obtained from the bark, used for cordage. A blue dye is obtained from the leaves. The seed contains 12.4% of a fatty oil. The plant can be grown as a hedge. The plant has an extensive root system and can be used for erosion control, especially on marginal land.
Habitat
Not known
Native range
E. Asia - China.