How to Prune a Spanish Broom Plant
- 1). Wipe the blades of your shears with a cloth dipped in alcohol. This treatment kills disease agents that may be on the tool and might infect the Spanish broom.
- 2). Thin overgrown Spanish broom in the dormant season over a four-year cycle. Cut 1/4 of the largest stems in the center of the plant to within 1 or 2 inches of the surface. The twigs regrow and produce more flowers than older branches.
- 3). Repeat pruning the next three dormant seasons, removing 1/4 of old, thick stems annually.
- 4). Begin the pruning cycle again in the fifth year. Just before spring starts, cut back the first fourth of the stems you pruned four years earlier.
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