ASHS Press Releases

American Society for Horticultural Science

  • Increase font size
  • Default font size
  • Decrease font size
Home HortScience Calla Lily Stands up to Salt
E-mail Print

BALTIMORE, MD - Ornamental plants are subjected to salt stress from a wide range of sources, including overfertilization, compost or manure with high salt concentrations, brackish irrigation water, and exposure to deicing salts. According to the authors of a study published in HortScience say developing a working knowledge of how salinity affects plant quality is particularly important with ornamentals grown for use as cut flowers or landscape plants. "Salt stress can have a major impact on plants' visual quality, therefore reducing marketability," explained Loyola University biologists Maren Veatch-Blohm and Lindsay Morningstar. The team researched the effects of salinity on shoot growth and flower production of calla lilies.

Four calla lily cultivars were used in the experiments. The plants were watered once a week with 300 mL of one of the three treatments: control (0 mM NaCl), medium salinity (25 mM NaCl), and high salinity (50 mM NaCl). Following irrigation the team collected the effluent from the soil and measured electrical conductivity (EC) to estimate change in the soil salinity.

Salinity applied post-emergence did not significantly affect shoot growth in either the medium or high salinity treatments. The most drastic effect on flower production was observed when the 50-mM treatment was applied pre-emergence; irrigation with the high saline solution significantly reduced dry weight and flower production compared to the other treatments. The authors observed that calla lilies subjected to the high saline treatment produced 50% fewer flowers than those in the other treatment groups.

Additional data showed that although shoots of the salt-stressed plants had a salt content two to five times greater than the control, the plants in all treatments maintained good visual quality and high relative water content. "We hypothesize that the maintenance of visual quality may in part be the result of increased Ca2+ concentration (up to four times the amount in the control) in the shoots of the salt stressed plants, which may have helped maintain turgor and cell membrane integrity under saline conditions," said Veatch-Blohm.

The experiments proved that irrigation water with a higher EC can be used without sacrificing plant quality.

"Our results indicated that use of irrigation water with an electrical conductivity more than twice that recommended for optimal calla lily growth can be used without a loss in plant quality," noted Veatch-Blohm. "This information increases irrigation options for these ornamentals, particularly in areas where high-quality water is scarce."


The complete study and abstract are available on the ASHS HortScience electronic journal web site:

Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at


Original Article:

Calla Lily Growth and Development Under Saline Irrigation
Maren E. Veatch-Blohm and Lindsay Morningstar
HortScience 46:222–227. [Abstract] [Full Text] [PDF]

Corresponding author. E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it