Sweet broom (Genista racemosa Cytisus spachianus) is a landscape shrub known for its pretty spikes of fragrant yellow flowers in the spring. The plant is native to the Canary Islands where the subtropical climate combined with the mountainous region creates a fertile environment for the plant. However, sweet broom does not tolerate high heat and grows best in the USDA growing zones 8 through 10.
Give the shrub at least eight hours of sunlight and space to grow. It will reach heights between 5 and 8 feet and widths between 5 and 10 feet, so keep neighboring plants away that might crowd it later.
Prune off the spent flower stalks using a clean pair of pruning shears to keep the bush from becoming straggly. The evergreen leaves will accent your garden throughout the year. Remove any dead or broken parts of the plant.
Water the sweet broom once a month in the absence of rain. Generally, most growing areas will have more than enough rainfall to meet the watering requirements of a sweet broom plant.
Fertilize the sweet broom with a balanced fertilizer in the spring before the blossoms open if you notice the plant is not growing as rapidly as it should or if you have poor soil. Cover the bare soil around the plant with 2 to 4 inches of any organic material to help conserve moisture and enrich the soil.