How FreezePruf Works Buy FreezePruf FreezePruf Technical Information Ask Dr. Franko FreezePruf News Contact Us

How FreezePruf Acts as a Frost/Freeze Protectant and “Zone Extender” in Plants

Plant structure

  1. FreezePruf surfactant ingredient allows formula to rapidly penetrate waxy cuticle and epidermis of leaves, flowers or fruit
  2. Once formula has entered the plant and the surface is dry, FreezePruf’s antidessicant ingredient reduces water loss from plant structures and the wash-off of formulation for up to 4 to 6 weeks.
  3. FreezePruf’s low molecular weight cryoprotectant partitions between cell interiors and exterior spaces, lowering the freezing point of both compartments.
  4. FreezePruf’s high molecular weight cryoprotectant stays outside the cells, lowering the freezing point of the extracellular water. It also pulls water from cells via non-destructive cytorrhysis, thus lowering the cell interior’s freezing point. Importantly, the high-molecular-weight cryoprotectant interacts with cell membranes to make them more resistant to damage from ice crystals when they do form, thus increasing the freeze tolerance of even cold-hardy plants.
  5. FreezePruf’s silicate-based ingredient binds to cell walls, thus strengthening them against ice crystal damage, thus increasing the freeze tolerance of cold-hardy plants.
  6. FreezePruf ingredients are transportable within the plant body.

FreezePruf (and Mother Nature) effect different plants – differently.
Here’s why...

1. FreezePruf adds to a plant’s natural ability to tolerate cold. Plant species vary greatly in their natural ability to tolerate cold (See Plant Groups below), and there is considerable individual variation even within a cultivar or variety.

2. A plant’s health and prior care effect how well it will tolerate cold. A drought-stressed or diseased plant, or a tropical plant that is already experiencing seasonal senescence (yellowing of leaves, brown leaf tips, etc.) due to shorter days and cooler nights, will not respond as well to FreezePruf.

3. Both the duration and intensity of the cold event will effect a plant’s and FreezePruf’s performance. Each frost or freeze event is unique in terms of duration and intensity of cold, wind chill factor, relative humidity, snow and ice cover, minimum temperatures and total time below freezing. Even within an individual landscape, microclimates occur and low temperatures can easily vary by several degrees.

So, how well will FreezePruf work on your plants, in your own garden and landscape?

In general, FreezePruf will add approximately 4 to 6˚ Fahrenheit to published hardiness values of plants (about the equivalent of ½ of a USDA Zone rating) (see listings below). The overall improvement range is approximately 2 to 3˚ F (¼ of a Zone equivalent) to more than 8 to 9˚ F (¾ of a Zone equivalent) over untreated plants that experience the same intensity (low temperature) and duration of cold, windchill, snow/ice cover, and other variables.

The following is a generalized grouping of popular garden and landscape plants organized by their ability to tolerate cold as reflected in their USDA Plant Hardiness Zone rating. For plants that are not specifically listed, consult the cold tolerance information on the ID label that came with your plant or any reputable gardening or landscaping reference book that describes your plant’s normal cold hardiness rating. FreezePruf is not intended for use on succulents


FreezePruf Plant Effectiveness Guide

Plant Group 1: Tender tropical plants (USDA Zone rating 10-11) and new spring foliage and flowers of evergreen and deciduous trees and shrubs that are intolerant of any frost. Includes... The foliage and flowers of many popular annuals and frost-sensitive perennial ornamental plants (coleus, begonia, impatiens, bananas, cannas, elephant ear, Mandevilla, peace lily, hydrangea, lantana, etc.), tender vegetables (tomatoes, eggplant, peppers, cucumbers, squash, etc.), many tender culinary herbs (cilantro, oregano, basil, etc.); and the newly-emerging leaves and flowers that appear in early spring with most popular deciduous and evergreen trees and shrubs (dogwoods, maples, azaleas, peaches, pears, ash, figs, deciduous magnolias, crape myrtles, etc.).

Plant Group 3: Warm-temperate plants (USDA Zone rating 7-8) that tolerate longer-term cold and winter minimum temperatures ranging from 10 to 20° Fahrenheit (Zone 8) to 0 to 10° F (Zone 7). Includes... Palms (cabbage palm, windmill palm, pindo palm, Mediterranean fan palm, dwarf palmetto, etc.) and a wide variety of Zone 7 and 8 broad- leaved evergreens, including Camellia sasanqua cultivars, Fatsia japonica, live oak, Southern magnolia, and others).

Plant Group 2: Subtropical plants (USDA Zone rating 9a and 9b), hardier perennial bedding plants, and the flowers and new growth of winter-blooming evergreens that will tolerate frost and short-term hard freeze events without extensive protection. Includes... Many citrus varieties (Satsuma mandarin oranges, Meyer lemon, kumquats, and other cold-tolerant citrus, etc.), hardier bedding plants and vegetables (snapdragons, columbines, mums, pansies, chives, parsley, peas, etc.), flowering evergreens (Camellia japonica cultivars, philodendron, loquat, oleander, Awabuki viburnum, Knock-Out roses and other cold-tolerant varieties, etc.), palms (Mexican fan palm, Canary Island date palm, sago palm, and other Zone 9 palms and cycads). Plant Group 4: Plants with USDA Zone ratings of Zone 6 (winter minimum 0 to -10° F) and colder. Includes... Many needle-leaved evergreens, hardy evergreen hollies and boxwoods, and the hardiest cultivars of Southern magnolia (“Bracken’s Brown Beauty” and “Edith Bogue”, etc.), and needle palms.