The Siberian pea shrub is a perennial plant that does not require much maintenance, can withstand harsh weather conditions, and often lives for many years. It is native to Siberia and Manchuria; in some countries where it has spread quickly by seed population, it is considered an ecological threat. The plant can develop yellowish flowers that, by the end of the season, turn into pods that may burst open to reveal the “pea” or small seed. The Siberian pea shrub or pea tree is also known by its Latin name, Caragana arborescens.
One can purchase this plant from many nurseries, though cultivation is considered fairly easy as well. A gardener could collect the unripe pods from a bush during late spring or early summer and crack them open to get to the seeds. The seeds do not tend to last long in this state, though, and should be sown quickly in a cold frame. Cuttings from a living shrub can also be used to start a new plant.
A Siberian pea shrub may live for many years and could reach a height of 10 to 15 feet (3 to 4.5 meters). The plant is able to endure cold temperatures as well as drought. Optimal conditions include lots of direct sunlight, though the pea tree can also grow in shaded areas.
The rugged nature of the shrub has made it a regular choice for ornamental and bordering purposes for many years. Although the seeds are said to taste bad, they are edible and sometimes fed to animals. This makes the plant a food option for wildlife and some livestock.
Only recently has the Siberian pea shrub been labeled a disturbance to certain ecosystems. The plant often invades grasslands, savannas, and woodlands. It has been perceived as a threat to native plant life in those areas, and measures have been taken to rid those areas of the pea tree.
The pea shrub is tenacious, however, and tends to spread quickly once birds and other animals begin to eat the seeds. Their waste, which contains the seeds amongst fertilizer, can cause more shrubs to pop up. To get rid of a Siberian pea shrub, it is often necessary to cut the shrub down and burn the stump or treat it with chemicals.
The long-lasting Siberian pea tree has its place as a useful plant in some cultures. The bark is rich in fiber and can produce a dark blue dye. In its native land, where the plant may be referred to as ning tiao, it is believed to ward off gynecological disorders and even breast cancer. These claims have not, however, been supported by substantial lab tests.