How to Prune a Broom Bush
Brooms are a group of shrubs in the bean family. Common broom species include Spanish broom (Spartium junceum) and Scotch, or common, broom (Cytisus scoparius). The Scotch broom is larger than the Spanish broom and has arching stems. Both species bloom yellow flowers. Brooms are easy to care for, requiring little water and no fertilizer. Some states, such as California, have listed these brooms as invasive plants. In Oregon, it is illegal to propagate or sell the Scotch broom. Prune the broom bush after it finishes flowering.
Go through the bush removing dead and damaged wood, especially that toward the center of the bush. Cut these canes back to their points of origin.
Remove branches or stems that cross over others and any that protrude from the shape you desire for the bush.
Pinch 1/2 inch from the tips of new growth when it reaches 2 inches in length. This prompts the broom to produce a new branch directly beneath the pinch portion, making the shrub bushier.
Rejuvenate Scotch or Spanish broom by cutting or mowing it to the soil while it is dormant. It will rapidly grow back, producing new, strong stems.
Prune A Scotch Broom Shrub
Trim back the tops of scotch broom in the garden by one-quarter of their length with pruning shears as flowers fade and before seed pods form in late spring. Prune out old, woody inner stems of garden scotch broom that die back as the plant grows with hand pruners. This dead, dry material creates a fire hazard. Even is seed pods are only small and green, they continue to ripen even after the plant is cut. Cut plants back that have begun to set seed and leave them in place to burn when conditions permit.
To discourage pests and disease, bag and dispose of all pruning debris.
- Oregon Department of Forestry; Community Tree Connections; July 2010
- "Illustrated Guide to Pruning"; Ed Gilman; 2002
- Fine Gardening: Cytisus Scoparius
- University of California Extension: Get a Handle on Broom
- Fire Safe Council of Nevada County: Scotch Broom Challenge
- Broombusters: Cut Broom in Bloom
- National Gardening Association: Pruning Scotch Broom
- Shrubs: Easy Plants for More Beautiful Gardens; Frances Tennenbaum