Gardeners who wish to have a thriving garden near a sea coast must consider the effects of salt spray on their plants. Coastal winds carry mist from waves inland, where salt builds up in the soil and on plants. Excessive salt causes foliage to lose moisture through a process known as exosmosis, which can lead to leaf burn or defoliation, especially in young plants. If you live within one-eighth mile of the ocean, choose salt-resistant species to avoid plant damage.
The wax myrtle (Myrica cerifera) is an evergreen that tolerates high amounts of salt. This tree grows to 20 feet tall with an equal spread. Wax myrtles can thrive in range of soils, from moist to dry, and tolerate full sun to partial shade.
The willow oak (Quercus phellos) is a highly salt tolerant, deciduous tree. Willow oaks grow between 80 to 100 feet tall with a 50-foot spread. Plant willow oaks in full sun and moist to well-drained soil.
Other salt-tolerant trees include the frangipani (Plumeria spp.), mahogany (Swietenia mahogani), Eastern red cedar (Juniperus virginiana) and Southern magnolia (Magnolia grandiflora).
Salt-tolerant shrubs include dwarf pittosporum (Pittosporum tobira). An evergreen, this hardy shrub also tolerates drought. Pittosporum grows to 8 feet with an equal spread. Dwarf cultivars, such as 'Wheeler's Dwarf', 'Mojo' and 'Cream de Mint' are highly salt tolerant. These small shrubs only grow to 4 feet.
The rugosa rose (Rosa rugosa) grows to 5 feet tall and 6 feet wide. This spreading deciduous shrub thrives in full sun and well-drained soil. Rugosa roses produce fragrant white to pink flowers in summer.
Other salt-resistant shrubs include inkberry (Scaevola plumieri), oleander (Nerium oleander), sea grape (Coccoloba uvifera) and rosemary (Rosmarinus officinalis).
Salt-resistant perennials include the blanket flower (Gaillardia pulchella). A drought-tolerant, sun-loving plant, blanket flowers grows up to 2 feet tall and produces red to orange blossoms.
Lantana (Lantana camara) also tolerates salty conditions. Lantana thrives in full sun and dry soils. This 2- to 4-foot plant blooms with multicoloured clusters of tiny red, yellow, pink to orange flowers.
Other salt-tolerant perennials include cape honeysuckle (Tecomaria capensis), daylily (Hemerocallis spp.) and seaside goldenrod (Solidago semperviren).
Ground covers that tolerate salt include golden stonecrop (Sedum acre), which is a tiny, deciduous plant that grows from 4 to 6 inches tall. Golden stonecrop is a good choice for rock gardens. It does best in well-drained soil and can grow in sun to partial shade.
Confederate jasmine (Trachelospermum jasminoides) is an evergreen which can spread out or grow up, like a vine. This fast-growing plant does best in full sun and produces fragrant, white blossoms in spring.
Other salt-tolerant ground covers include English ivy (Hedera helix), lily turf (Ophiopogon japonicus), spreading liriope (Lirope spicata) and mondo grass (Ophiopogon japonicus).