Broom Plant Care: How to Grow Broom Plants

Broom plant is the common name for two plant species classified as Cytisus and Genista, which belong to the legume family (Fabaceae). The broom plant comes in many varieties of evergreen and deciduous shrubs. While bright yellow flowers are the most common feature of broom plants, the flower color may also be red or orange depending on the variety. Beyond the visual appeal, the broom plant has also been used for erosion control. Different types of broom plants include Spanish broom (aka Spanish gorse), French broom, English broom, Portuguese broom, and Scotch broom (also called common broom).

Native to Europe and parts of Africa, Scotch broom was brought to North America in the nineteenth century. Today, it grows on hillsides and roadsides throughout the Pacific Northwest. These shrubs are drought-tolerant and experience rapid growth in late spring and early summer, which has led some states to classify them as noxious weeds. Be aware that broom plants are toxic to humans, cats, and dogs. Exercise caution when growing these shrubs.

With the right care, your mature plants can reach up to ten feet in height.

1. 1. Check your planting zone and local laws. Broom plants grow best in USDA hardiness zones five through eight. However, certain broom plant varieties are also considered invasive species in some of these areas and may crowd out native plants. Check your local laws to make sure the variety you’re interested in isn’t considered an invasive plant in your region.
2. 2. Plant broom plants in full sun. Broom plants thrive in full sun and do not grow well in shade. Keeping your broom plant in a shaded area will result in fewer wildflower blooms.
3. 3. Use well-draining, acidic soil. Loamy soil is ideal for broom plants, while dry, sandy soils are not ideal. However, certain varieties—like the sweet broom plant (Cytisus racemosus syn. Genista racemosa)—are relatively hardy and can thrive in poor soil and disturbed areas. If your plants seem to be struggling in alkaline soil, add compost in the early spring for a nutrient boost.
4. 4. Give your broom plant adequate water. Water your broom plant regularly during its first year of growth to help it establish a strong root system. Give your broom plant extra water during more intense periods of heat like late summer and add mulch around the base of the plant to help retain moisture.
5. 5. Prune your plant in the spring and summer. Avoid pruning your broom plant in the autumn or winter, but do prune your broom plant in the spring and summer to encourage new growth. Use a clean pair of gardening shears at a forty-five-degree angle rather than cutting stems straight across, as this can cause the green stems to rot.
6. 6. Avoid adding clippings to your compost pile. Unless you want broom plants to spread throughout your yard, avoid tossing the plant clippings in your compost pile. The broom plant reproduces via seed pods and germination can occur in nutrient-rich compost. Discard broom plant clippings in the trash instead.
7. 7. Treat pest infestations. Sweet brooms are susceptible to caterpillar infestations. Spray your broom plants with a diluted mixture of soap and water to kill the caterpillars and their eggs. Apply neem oil spray to stubborn infestations.

Grow your own garden with Ron Finley, the self-described "Gangster Gardener." Get the MasterClass Annual Membership and learn how to cultivate fresh herbs and vegetables, keep your house plants alive, and use compost to make your community—and the world—a better place.