Developed by Dr. David Francko and other botanists, water-based FreezePruf spray reduces the freezing point of water inside plant tissues. When sprayed onto trees, shrubs, flowers and other plants, FreezePruf coats leaves with a wax-like coating that allows plant parts to freeze solid and still remain viable, offering invaluable protection for temperature drops beyond the norm. "It's like moving your whole home landscape about 200 miles farther south," Francko told Science Daily. "That's about the effect that you get, anywhere from 3 to 10 degrees more cold tolerance." -- roughly the equivalent of half a USDA Zone.
For gardeners, Science Daily's announcement in November 2008 of a spray "like anti-freeze for your plants" sounded too good to be true. Five biodegradable ingredients work together to protect plants from freezing, Science Daily reported, allowing them to "endure temperatures 2.2 to 9.4 degrees Fahrenheit colder than it would without the spray," the degree of protection depending upon the species. Not only are the claims true, but this plant anti-freeze is safe for children and pets and you can buy it at better nurseries everywhere.
How it Works
A surfactant allows the formula to penetrate the protective waxy cuticle and epidermis cells, or "skin," of leaves, flowers and fruit. Once FreezePruf enters plant cells and dries on the plant's outer surfaces, an antidessicant protects the plant from water loss and prevents the spray from washing off. Then one freeze protector partitions cell interiors and exteriors -- lowering the freezing point of both -- and another interacts with cell membranes to make them more resistant to damage from ice crystals. A silicate-based ingredient binds to cell walls to further strengthen them against ice crystal damage.
For best results, spray FreezePruf on plants when temperatures are above 50 degrees F., at least eight to 12 hours before an expected freeze. Alternatively, apply it seasonally, anticipating cold temperatures within the next four weeks. Spray FreezePruf liberally over the entire plant, concentrating the formula on tender buds and blooms on fruit trees or on tender new growth of other hardy trees. With normal precipitation, protection lasts up to four weeks, but if rain or snow is heavy it should be applied again after two weeks. Reapply as new growth appears.
Increased exposure to cold increases plant cold tolerance -- up to a point -- so don't pamper your plants. Acclimate them to cold to enhance their survival prospects. But put out all the stops when a "cold event" threatens their survival. Use FreezePruf in conjunction with other frost-protection measures for the greatest possible cold protection in dire circumstances. Make sure trees are well watered and thoroughly hydrated. Cover them with old blankets or frost cloth -- covering but not touching foliage -- and also supply some source of heat. Stringing Christmas lights on plants works, as does hanging light bulbs in outdoors-safe fixtures from the lowest branches of a covered tree. Some people use kerosene or propane heaters beneath covered tree canopies.
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