Caragana arborescens, or the "Siberian peashrub," is a tall shrub, native to Siberia and Mongolia. It was imported to the United States in the 1700s as an ornamental plant. Its ability to grow in poor conditions, including alkaline and salt-contaminated soils, drought, cold winters and partial shade made it a desirable windbreak in the north-central states. Despite its status as an invasive species, with careful management and pruning you can make it a lovely windbreak, hedge or small tree.
Things You'll Need
Wait until the caragana finishes blooming. Many flowering shrubs, including caragana, azalea and lilac, require pruning after flowering. If you prune in the winter, you will remove the flower buds.
Thin the branches to open up the center of the shrub. If you're encouraging a treelike growth, remove the lowest branches, cutting 1/2 inch from the main trunk with the lopping shears.
Reduce the size of the caragana by pruning. Shorten overgrown and too-long branches to shape the caragana, using either the lopping shears or the hand shears. Hand shears are suited for small branches, generally less than 1/4 inch in diameter.
Trim the smallest branches at different lengths to avoid a "haircut" look.
Allow the shrub to retain most of its natural shape.
Prune to reduce the size of the shrub and remove damaged, weak or overgrown branches.
Shape the shrub as it grows. Prune a little each year; do not prune severely after several years.
Wear a long-sleeve shirt, pants, gloves and safety glasses when pruning.
Caragana is an invasive species when grown under optimum conditions. Remove seed pods if possible and seedlings as quickly as possible.
- Purdue Department of Horticulture; Pruning Ornamental Trees and Shrubs; Michael Dana, et al.; April 2001
- North Dakota Department of Agriculture: Caragana (Caragana arborescens)
- North Dakota State University: Caragana or Siberian Peashrub
- USDA Natural Resources Conservation Services: Conservation Plant Characteristics
- Montana Plant Life: Siberian Pea-Shrub