A new, biodegradable foliar/floral spray that increases plant resistance to both cold damage and cold mortality has been introduced to the commercial market. The spray improved cold tolerance by approximately 2°F to 9°F, depending on the variety of plant and the duration/ intensity of frost or freeze. Use of the non-toxic spray could add the equivalent of approximately 0.25 to almost 1.0 USDA Plant Hardiness Zone to the cold hardiness rating of plants.