Brooms (species and cultivars of Cytisus scoparius) are fast growing but short-lived shrubs. Their life and flowering performance can be extended by pruning spent flowers to avoid the production of seed. Broom flowers in the spring on wood produced in the previous year. Pruning aims to encourage new wood for the following year's flowers.
Prune established plants immediately after flowering in early to mid-summer.
Cut out the spent flowers reducing the flowering stems by two-thirds of the previous year's growth.
Avoid cutting back too hard as new shoots will not be produced when plants are cut back into old wood. Old or overgrown plants are best replaced.
Young plants should be pinched out to encourage a bushy habit.