Figs. 1-6. No plants like salty soil but some will tolerate it. Salt-tolerant shrubs include (shown top to bottom, left to right) caragana, buffaloberry, common lilac, golden currant, skunkbush sumac and juniper.

Plants hate salty soil and landscaping in these soils is a challenge. The salts will burn plant roots and prevent them from absorbing water needed for healthy growth. Salts lead to compacted ground with poor aeration and poor drainage.

Young plants are especially sensitive. Scorched leaf margins and needle tips are the initial symptoms of distress.

The best way to cope with a salty soil is to grow plants that tolerate it. Among leafy shrubs, the most tolerant plants include caragana, buffaloberry, silverberry, sea buckthorn, common lilac, golden currant, ‘Freedom’ honeysuckle and skunkbush sumac (Figs. 1–5). The best evergreen shrubs are junipers; these include Rocky Mountain juniper and Eastern red cedar (Fig. 6).

The most tolerant leafy trees include green ash and Russian olive. These trees are found in abundance across the state but are rarely used in landscapes today. Leafy trees with moderate tolerance to salty soil include honeylocust, catalpa, coffeetree, corktree and hawthorn. Ponderosa pine is the most tolerant evergreen tree used in North Dakota landscapes, but spruces and other pines show some tolerance.

We can take some steps in our landscape practices to minimize the impacts of saline soil:

Irrigate deeply and infrequently, rather than shallowly and frequently. In most cases, a single irrigation of one inch of water per week is sufficient for healthy growth. Deep watering promotes a deep root system and flushes harmful salts away from roots.

Mulch your plants. This will reduce evaporation, which leads to the accumulation of salts.

Fertilize plants only when needed. Fertilizers contain salts.

Add organic matter (compost or sphagnum peat moss). In new landscapes, you can an inch of organic matter and till it into the soil. In established landscapes, one strategy is to core aerate the soil, filling the holes with organic matter.

Flush out salts when they appear on the surface. Apply 2 inches of water over a 2–3 hour period, stopping if runoff occurs. Repeat again in 3 days if the salts reappear. 

Sources:

Appleton, B., V. Greene, A. Smith, S. French, B. Kane, L. Fox, A. Downing and T. Gilland. 2005. Trees and shrubs that tolerate saline soils and salt spray drift. Virginia Tech:Blacksburg.

Herman, D.E. and V.C. Quan. 2006. Trees and shrubs for Northern Great Plains landscapes. North Dakota St. Univ.:Fargo.

Written by Tom Kalb, Extension Horticulturist, North Dakota State University. Published in the NDSU Yard & Garden Report, August 21, 2016. Photos were made available under Creative Commons licenses specified by the photographers: pverdonk, Julia Adamson, Martin LaBar, amy_buthod, Leah Grunzke, Peter Gorman.