In order to use reclaimed water to irrigate landscape plants and minimize damage and loss, salinity tolerance of commonly used landscape plants needs to be identified and characterized. Eight herbaceous perennials and groundcovers were obtained from a nursery, transplanted to 2.6-L plastic containers, and grown in the greenhouse for 2 weeks before salinity treatments (1.0, 3.2, 6.4, and 12 dS·m-1) were initiated. Plants were irrigated with measured amounts of saline solutions to obtain a 30% leaching when ≈50% water was depleted. After 12 weeks, half of the plants in each treatment were destructively harvested and dry weights of shoots and roots were taken. Three Penstemon species (pseudospectabilis, eatoni, and strictus) and Lavandula angustifoliaat 6.4 and 12 dS·m-1 and most of them at 3.2 dS/m did not survive. Shoot dry weight of Delosperma cooperidecreased by 25% at 12 dS·m–1, but there were no significant differences among the rest of the treatments. All plants of Teucrium chamaedryssurvived, but growth was reduced significantly with lower visual scores as salinity of irrigation water increased. Although growth was reduced in Gazaniarigensas salinity increased, no other signs of stress were observed. Ceratostigma plumbaginoides had less growth at 3.2 dS·m–1, and older leaves showed reddish pigmentation at 6.4 dS·m-1, whereas those at 12 dS·m-1 did not survive. Among the tested species, D.cooperiand G.rigensindicated a high tolerance to salinity; T. chamaedrysand C. plumbaginoides were moderately tolerant; and the rest were salt sensitive.
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