
Growing a garden full of healthy and beautiful plants is dependent on a few basic growing conditions. Among these are suitable soil and water for nutrition and hydration. Sometimes, especially in coastal areas, soil becomes contaminated with saltwater, compromising plant health. Fortunately, gardeners dealing with the effects of saltwater on plants can learn how to help their gardens stay healthy.
Damage
Saltwater damages plants when salt is taken into plant tissues. The salt builds up, interfering with plant processes. Saltwater also deprives plants of water by inhibiting the process of osmosis, whereby water easily passes through root tissues into the plant.
Sources of Contamination
Soil can become contaminated by saltwater through coastal or tidal flooding, and by rising water tables. An abundance of salt spray can also contaminate soil as it washes off sidewalks, patios and plant surfaces into the soil.
Symptoms
Plants suffering from saline toxicity in soil show brown leaf margins. Sometimes they turn yellow with green veins (chlorosis). As chlorosis progresses, leaves can turn brown or black and fall off. A general decline of health and death can follow. Salt spray can cause brown spots on plant leaves, sometimes damaging them.
Prevention/Remedies
Grow plants in well-drained soil, which allows fresh water to wash salt out. Fertilize plants only when needed and according to label directions to avoid contributing fertilizer minerals to soil salinity. If your water table is rising, raise the garden beds, using plenty of organic matter and sand to improve drainage.
Plant Selection
Choose plants that tolerate saline soils. Salt-tolerant trees include Russian olive, Leyland cypress, yaupon holly, and southern magnolia. Shrubs include rosemary, rugosa rose, forsythia, rose of sharon and bigleaf (common) hydrangea. Many ornamental grasses are salt-tolerant, including pampas grass, maiden grass and Muhlygrass. Salt-tolerant perennials include daylily, lantana and blanket flower.