About the difference the plant makes

Different types of plants vary considerably in their tolerances to the total amount of salt and to concentrations of sodium, chloride, and boron. For instance, turf grasses, most annuals, and deciduous plants typically tolerate more salt than evergreens do. Because they are frequently mowed, turf grasses do not normally accumulate high levels of salt. Also, they usually tolerate more sodium, chloride, and boron than other types of plants. Most annuals do not accumulate high levels of salt within their yearly life span. Many deciduous plants do not accumulate salt in their leaves, as they shed their leaves every autumn.

Different species of plants also vary in their tolerance to total salt and to sodium, chloride, and boron. The more tolerant species are better able to adjust osmotically and to extract more water in the presence of a moderate to high amount of total salt and moderate to high concentrations of sodium, chloride, and boron. Examples of extremely tolerant plants include Alkali Sacaton grass, the Mexican Pinon pine tree, the Norfolk Island pine tree, Oleander, and Red Apple ice plant. All of these plants can tolerate 10 decisiemens per meter or more. When irrigated with such saline water, they require no more than a routine amount of management. If possible, choose a tolerant plant in the first place or replace a less tolerant plant with a more tolerant one.

Tolerances to salt of selected turf grasses and other landscape plants

Sensitive	Moderately Sensitive	Moderately Tolerant	Tolerant
annual bluegrass	annual ryegrass	blue decaena	alkaligrass
colonial bentgrass	coast redwood	coast live oak	Bermuda grass
cotoneaster	cork oak	European fan palm	bougainvillea
crape myrtle	creeping bentgrass	forsythia	brush cherry
ginkgo	fine-leaf fescue	frangipani	Chinese tallow tree
Kentucky bluegrass	Italian cypress	oleander	croceum ice plant
liquidambar	Japanese boxwood	perennial ryegrass	evergreen pear
Oregon grape	orchid sage	rosemary	Mexican stone pine
photinia	southern magnolia	tall fescue	Norfolk Island pine
Pyrenees	xylosma	weeping bottlebrush	seashore paspalum
star jasmine	yellow sage	zoysiagrass	white/purple ice plant

For many plants, tolerance to salt or to sodium, chloride, or boron also varies, depending on the plant's stage of growth. Some plants are less tolerant when germinating and emerging and more tolerant when established and mature. Minimizing such a plant's exposure during the more sensitive stages of its life cycle may help to mitigate the effects of salt. Leaching salt from the intended root zone before planting is one way to do so. Another is to irrigate enough to prevent the soil from drying while the plant is becoming established. When a soil dries, salt may become concentrated closer to the plants' roots.

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