Salt Tolerant Plants

If you live on or very near the beach, choose salt-tolerant native plants for your landscape. Salt-tolerant is a broad term that describes plants that can thrive in places subject to salt spray, salt water inundation, or salt water intrusion into shallow wells used for irrigation.

Three general beach areas require different levels of salt-tolerance in plants. The frontal zone extends from the high-tide line to areas of the beach in which the sand is stable. Native grasses and trailing vines do well here and are the only plants that can handle the salt spray and drifting sand. The back dune, where the sand is stable, supports a select group of native salt-tolerant trees, shrubs, and other herbaceous plants as well as native grasses and vines. Farthest from the beach is the forest zone where pines and oaks and other hardwoods grow.

If you have shoreline and want to plant on the bare sands of the frontal zone, choose sand-colonizing plants (see Chart). Plants in this zone must be able to tolerate shifting sand and salt spray. Salt-tolerant grass species and creeping, colonizing vines thrive in this zone.

Very few native trees and shrubs do well just shoreward of the frontal zone into the back zone. This is still a tough area for plants. Sands are fairly stable here but salt spray is still intense since there is no buffer between these plants and winds blowing off the water. Further inland into the back zone, where wind and salt spray are not constant, sabal palm, sea grape (south Florida), and sand live oak (north Florida) will grow. These are the only shade-providing trees for this area of the beach. Tropical storms, however, can still cause considerable damage to plants in this area.

Sabal palms planted in clusters of five to seven individuals will shade patios and sitting areas located on back dunes and further inland. They transplant easily. Choose individuals of varying heights for a natural look. They are cold-hardy and are probably the most hurricane-resistant plants in Florida.

Sea grapes make wonderful small trees. They can grow to twenty-five feet tall and provide dense shade. You can remove the lower branches and allow the upper canopy to grow either as a single trunk or a multi-trunked tree. The leaves will turn orange-brown and fall off after being buffeted with salt-laden air from a storm, but the plant refoliates quickly. This in not the ideal plant for open pool areas, but in other areas fallen leaves make a long-lasting mulch.

Sand live oak is a shrubby evergreen tree. It has shiny, dark-green, leathery leaves and gnarled branches. You can intersperse it with sabal palms to create a more natural look.

Shrubs adapted to this area of the beach, such as yaupon holly, will most likely be stunted and shaped by wind and salt spray into interesting configurations. During storms they may lose their leaves, but will refoliate. Plants unable to withstand such conditions will not survive.

In the forest zone a variety of plants grow well (see chart). It is an area where dune plants, coastal species, and inland species intermix.

Other areas that require salt-tolerant plants are low lying areas near the beach, the land sides of sea walls and the banks of brackish creeks. Plants in these areas can occasionally be flooded by brackish water, and you need to choose plants that can survive salt water inundation (see chart).

Another problem that is becoming more common is salt water intrusion into shallow wells. Folks who live in coastal areas and who use shallow well water to irrigate their plants should have their water tested for salt levels. If you do have salt water intrusion, then you should stop using well water for irrigation unless you have salt-tolerant plants. Since even native plants require watering until they are acclimated, native plants that don't tolerate a moderate level of salt will not do well.

No section on salt-tolerant coastal plants would be complete without reference to mangrove trees. They grow naturally along the edges of saline bays and tidal streams. Mangroves are protected at the federal, state, and local levels in Florida, and the state and many local municipalities regulate mangrove trimming. Protect natural stands of mangroves on your property. Don't hedge mangroves to a six-foot height as currently allowed in many counties, since you will eliminate habitat for shoreline wildlife by doing this. Remember also, that mangroves protect your home and property against hurricane and storm force winds. A more environmentally sensitive approach is to remove only select branches in order to create desirable views.