On the barrier islands and along Gulf-access canals, salt reaches plants two ways: as spray carried on the wind, and through salty soil or irrigation water. Plants that aren't built for it brown at the edges, drop leaves, and decline.
Plants rated high for salt
For hedges and screens: sea grape, cocoplum and silver buttonwood. For palms: sabal, Florida thatch, coconut and bottle palm. For low color in sun: beach sunflower and native pineland lantana. Native muhly grass handles salt and drought and makes a soft, flowing border.
Placement matters
Put the toughest plants on the side facing the water or wind, where they shelter less tolerant plants behind them. Rinse leaves with fresh water after a big storm surge or a windy salt event if you can.
On the islands, check the rules
Sanibel has its own vegetation rules that favor native plants, and many island condo and HOA communities require approval for planting changes. Check before you start.