University of California

Calcium chloride reduces rain cracking in sweet cherries


Michael Rupert
Stephen Southwick
Kitren Weis
John Vikupitz
James Flore
Hong Zhou

Authors Affiliations

M. Rupert is Postgraduate Researcher, Department of Pomology, UC Davis; S. Southwick is Extension Pomologist, Department of Pomology, UC Davis; K. Weis is Postgraduate Researcher, Department of Pomology, UC Davis; J. Vikupitz is Product Manager, Netafim Irrigation, Inc., Fresno; J. Flore is Professor of Horticulture, Michigan State University; Zhou is Statistician, Department of Statistics, UC Davis.

Publication Information

Hilgardia 51(5):35-40. DOI:10.3733/ca.v051n05p35. September 1997.

PDF of full article, Cite this article


Rain cracking of sweet cherry fruit is a worldwide problem and has resulted in substantial crop losses of California cherries in each of the past 4 years (1993–1996). Various strategies to reduce cracking have provided inconsistent results. During 1996, however, rain-timed applications of calcium chloride (CaCl2) via overtree sprinklers reduced the overall percentage of rain-cracked ‘Bing’ cherry fruit by nearly half at three locations in the Central Valley. Although these results were obtained in only one season, their consistency across sites is encouraging. In addition, a preliminary observation suggests this calcium treatment may also reduce postharvest disorders of rain-exposed fruit without affecting fruit firmness, size or weight. Some marginal leaf necrosis was noted at one site, suggesting that application rates may need to be adjusted. Overtree delivery of calcium chloride during rain provides the potential for cherry growers to reduce fruit cullage from rain. While the setup and operational costs are substantial, the increases in marketable fruit may make this system a profitable investment.


Ackley WB. Fruit cracking of sweet cherries. Washington State University Progress in Agriculture and Home Economics Research, Progress Report No. 9 1956.

Ackley WB, Krueger WH. Overhead irrigation water quality and the cracking of sweet cherries. HortScience. 1980. 15(3):289-98.

Fernandez RT, Flore JA. Intermittent CaCl2 sprays during rain to prevent sweet cherry cracking. HortScience. 1995. 30(4):793-

Rupert M, Southwick S, Weis K, Vikupitz J, Flore J, Zhou H. 1997. Calcium chloride reduces rain cracking in sweet cherries. Hilgardia 51(5):35-40. DOI:10.3733/ca.v051n05p35
Webmaster Email: wsuckow@ucanr.edu