Recently I have received many phone calls from gardeners asking about the large, multistemmed shrub growing along the dry roadsides, covered in a mass of showy white flower heads. Since the tiny flowers each have a short stalk, without a doubt it has to be baccharis halimifolia, commonly called salt bush, groundsel tree or sea myrtle.
In the aster family, salt bush is native throughout Florida, west to Texas and north to Massachusetts in zones 5 to 9. An oval to rounded shrub growing 5- to 15-feet tall, it is useful in massed plantings along roadsides or the back of a flower bed. Black Diamond, a prestigious golfing community near Beverly Hills, boasts some of the finest specimens in the county. New Black Diamond residents Lois and Graham Lister planted groups of three salt bushes among the saw palmettos at the entrance to their unusual grassy driveway to provide a focal point in a naturalistic setting. Sugarmill Woods homeowner Cheryl Flis installed several of the same plants as an evergreen privacy screen and to provide cover, nest sites and seed for birds.
Salt bush grows along the brackish, wet coast to the dry, sandy uplands in either acid or alkaline soils. It thrives on only natural rainfall but tolerates irrigation too. Planted in full sun it will be shorter and more dense than if planted in part shade. It will become a small tree with gray-brown bark that can live as long as 50 years. Annually pruning out the older woody stems will regulate the height and keep the shrub rejuvenated.
Nipping the tips of branches in spring results in denser foliage and more flowers in the fall. Usually evergreen in Citrus County, the shiny to grayish-green leaves are 1- to 3-inches long, about half as wide and are often toothed near the top (apex).
If you see a baccharis along the coastal swales and beaches where the water is a brackish mix of salt and fresh water, it will probably be B. angustifolia, saltwater false willow with very narrow leaves. A third native species, silverling, B. glomeruliflora usually grows in flood plains and has stalkless flowers.
The best feature is baccharis' masses of fall flowers. Individual flowers are small but clustered in conspicuous, showy heads that last at least a month. Bushes are either male or female.
The males have lots of pollen for the bees and pollen gathering zebra longwing butterflies but do not have seeds. Female plants become a giant cloud of puffy white down in December. Small songbirds flock to my garden to feast on the tiny seed. Still there are many seedling salt bushes to harvest in the spring and pot up to stock my small nursery.
There are unproven stories that baccharis might be toxic to livestock or an allergen to sensitive people. As a hay fever sufferer, I have no ill effects from the salt bush or goldenrod I grow but I seek and destroy ragweed and dog fennel, which have a finer pollen that bothers me. The leaves are distasteful to me and probably domestic animals would also find them unpalatable.
There are many benefits to salt bush: pest resistance, frost hardiness, xeric or drought tolerant, easy to grow even in difficult soil situations, availability in the nursery trade, long life, no irrigation or fertilizer required, wildlife benefits and masses of white fall flowers. Salt bushes make an excellent addition to any garden.
Editor's note: This weekly article is provided by Jane Weber, professional gardener, grower, consultant, designer and environmentalist. Visit her Certified Florida Yard and Backyard Wildlife Habitat, 5019 W Stargazer Lane, Dunnellon. Call (352) 465-0649.