Sweet broom is also known as Easter broom or by its Latin name of Cytisus x. spachianus. It's a flowering deciduous shrub with upright arching branches, fan-like leaves and fragrant golden yellow blossoms that appear in late winter to early spring. Use sweet broom for dry hillside plantings, borders, ground cover or containers.
Plan the placement of your planting or container to allow for enough clearance to accommodate this fast-growing plant, which can reach 6 to 8 feet tall and 5 to 6 feet wide. Inspect new plants for whiteflies and spider mites, which are fond of sweet broom plants and can be found on the underside of foliage. Although some broom-plant species are considered invasive and banned in certain parts of the United States, this variety is a hybrid developed to be sterile and is under consideration in those same areas to see whether it will prove a safe alternative.
Plant sweet broom in a good general-purpose potting soil that drains well, adding sand or a mix of perlite and peat moss if it looks like the potting soil is packed too tightly. If you want to mix your own potting soil, take 1 part garden soil, 1 part coarse sand or perlite, 1 part moist peat or humus and a dusting of lime.
Feed your plant every two weeks with a water-soluble fertiliser, or you can apply once in early spring a granular slow-release fertiliser. Sweet broom plants are tolerant of poorer soils outdoors and can be helpful for stabilising slopes.
Use a regular watering schedule during the first growing season until the plant has developed a deep root system. Drench the soil with warm water and allow the soil to become moderately dry between waterings. Mist the plant occasionally with warm water during the flowering season.
Locate your plant in an area where it will receive light shade to full sun. It will do best in bright indirect sunlight coming from the south, east or west. It has a healthy frost tolerance down to -9.44 degrees Celsius.
Pruning and Propagation
Prune your sweet broom when it has finished blooming by trimming back all the branches by about one third. As the plant matures over a few years, cut the oldest woody stems all the way to the ground because they will not flower as well as the younger branches.
Propagate the plant by culling seeds or stem cuttings with the heels attached in spring or summer. Place the seeds or cuttings in a mixture of moist peat and perlite in a pot, then cover the pot with a plastic bag secured by a rubber band to keep the moisture in. Place your pot in indirect sunlight or under a fluorescent light and transplant when the seeds/cuttings have produced roots.