The name of this taxon is not universally accepted. Some authorities, such as the African Plants Database (http://www.ville-ge.ch/musinfo/bd/cjb/africa/details.php?langue=an&id=176784), treat it as a synonym of Colutea abyssinica Kunth & Bouché[].

Common Name:

General Information

Colutea istria is a much-branched, deciduous shrub usually growing 90 - 150cm tall but sometimes reaching 300cm[, ].
The plant is used in land reclamation projects in the Negev dessert. It is sometimes grown as an ornamental in gardens, where it can be used as a hedge.

Known Hazards

None known

Botanical References

,

Range

W. Asia - Syria, south through Arabia to northeast Africa.

Habitat

Rocky slopes and cliffs, near water springs; at elevations from 600 - 1,500 metres[]. Hard rock outcrops and wadis in shrub-steppes of Israel.

Properties

Other Uses Rating
Habit	Deciduous Shrub
Height	3.00 m
Pollinators	Bees
Cultivation Status	Wild

Cultivation Details

Colutea istria is a plant of Mediterranean to semi-arid and arid tropical climates - it is not very hardy in cooler regions of the temperate zone. It grows in climates where the summers are hot (with temperatures occasionally reaching as high as 46°c) - in such regions plants can tolerate occasional winter temperatures down to about -5°c for short periods so long as the soil is very well drained[]. In regions near the limits of its hardiness, such as southern Britain, plants can be grown successfully outdoors by a sunny wall[]. Plants can survive with as little as 90mm of rainfall in a year, which all falls in two months of the winter[].
Requires a well-drained soil in full sun[]. Grows well on dry sunny banks and in poor soils[, ]. Dislikes strong winds, though another entry in the same book says that it tolerates salt-laden winds[].
Flowers are produced on the current year's growth[].
The most distinctive character of the genus is the large, thin-walled, inflated pod, which, when half ripe, may be made to burst with a miniature report when squeezed[].
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[].

Edible Uses

None known

Medicinal

None known

Agroforestry Uses:

The plant is used in land reclamation projects in the Negev desert, consolidating soil and plant debris from flood waters[].
Plants respond well to trimming and can be grown as a hedge[].

Other Uses

None known

Propagation

Seed - pre-soak for 24 hours in hot water and sow late winter in a greenhouse[]. Scarification can help speed up the germination process[]. Germination can be slow and erratic[], though treated seed usually germinates in 1 - 3 months at 20°c[]. As soon as they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out in late spring or early summer, after the last expected frosts.
Cuttings of half-ripe wood, 7 - 10cm with a heel, mid summer in a frame[]. Cuttings are not very long-lived[].