Conocarpus erectus (Combretaceae)
Origin: coastal areas of Florida and the Caribbean to South America.
Coastal areas can be tricky to landscape. Salt is poison to most plants, and the difference between a true coastal native and a plant sold as “salt tolerant” at the nursery becomes very apparent after a tropical storm. The soil of coastal areas is also notoriously devoid of nutrients (unless you count salt as a nutrient), highly alkaline, and usually high in sand content – in other words, quick draining. Many coastal areas and small islands receive little rainfall compared to areas just onshore the mainland, and so oftentimes the soil is incredibly dry. Depending on tropical storms and tidal influence, however, an area which was just completely dry can be flooded suddenly and for a long time. So plants need to be both drought tolerant and flood tolerant. And did I mention salt tolerant?
Buttonwoods are perfectly adapted to growing along flooded coastline. Known as “Florida’s fourth mangrove,” they are not technically a mangrove, but closely associated. Mangroves have seeds which actually germinate on the parent plant before floating off to root in a new land; buttonwood seed is first dispersed and then germinates later, like most plants. They are a large-growing shrub or small tree, with a beautiful gnarled appearance at maturity – rough, craggy bark perfect for hosting epiphytes, and thick, twisted stems adding overall character. Older specimens resemble oak trees, beautifully sculpted by nautical winds and salt spray.
Buttonwoods have become a popular landscaping choice over the last few years, especially the silver variety, Conocarpus erectus var. sericeus, which is slightly less cold tolerant than the typical species. So popular has “silver buttonwood” become, in fact, that the species buttonwood is now referred to as “green buttonwood.” The silver variety is covered in a very fine and dense pubescence which gives the plant a silver sheen and color, and also attracts a black discoloration which resembles sooty mold in appearance. Buttonwood’s flowers are held in pendent spherical clusters, and are intensely fragrant, smelling of artificial grape. The plants bloom repeatedly throughout the year, and it is a common fragrance to catch while walking along Sarasota’s bayfront. The fruits are also spherical, resembling leather buttons, which is where the plant gets is common name from.
Here at the Marie Selby Botanical Gardens we have lots of coastline, and lots of buttonwood, especially around the northern end of our coastal lagoon. Come check them out, and keep your nose peeled for the smell of grape soda!
Text by David Troxell