Freeze and Frost Protection for Fruits and Vegetables

Apr 01, 2021

By K Crosby

A few key points for vegetables to keep in mind:

Plastic mulch will usually get you about 2 oF of additional protection when the plant canopy is very close to the plastic (as it is now) and it is sunny during the day.
Copper Sprays: Often used by growers with the idea of killing any ice nucleating bacteria on the leaf surface to prevent ice formation. This has been shown to work in controlled studies, but in the field there are often other factors that limit the effectiveness. One of which is that dirt and dust on the leaves can also be a source of ice nucleation. Many growers spray copper before a frost and in general it isn’t harmful. However, in some cases (watermelon), young seedlings (1 week or 1.5-week-old) can be susceptible to show phytotoxic response to copper.
Irrigation: Irrigating for freeze protection is mostly used on fruit and is covered in the attached publication. Pivot irrigation will not work for freeze protection BUT moist soil will tend to retain some heat from the day and can give a grower a little protection in the evening. If the soil is already wet then additional irrigation won’t help, but if it is dry, then adding some moisture to the soil can help give some protection.
Other sprays: A variety of other sprays (ie. Vapor Guard) are sold on the market for frost protection and the limited number of studies done on them indicates that they do not work. Here is the study done on tomato and pepper: Perry, K.B., Bonanno, A. R., & Monks, D.W. (1992). Two putative cryoprotectants do not provide frost and freeze protection in tomato and pepper. HortScience 27:26-27.
Row cover are the most effective option, but not economical for the large acreages we are working with.

Video: EP 73 Diversity is Resiliency – Stories of Regeneration Part 6

During the growing season of 2023 as summer turned into fall, the Rural Routes to Climate Solutions podcast and Regeneration Canada were on the final leg of the Stories of Regeneration tour. After covering most of the Prairies and most of central and eastern Canada in the summer, our months-long journey came to an end in Canada’s two most western provinces around harvest time.

This next phase of our journey brought us to Cawston, British Columbia, acclaimed as the Organic Farming Capital of Canada. At Snowy Mountain Farms, managed by Aaron Goddard and his family, you will find a 12-acre farm that boasts over 70 varieties of fruits such as cherries, apricots, peaches, plums, pears, apples, and quince. Aaron employs regenerative agriculture practices to cultivate and sustain living soils, which are essential for producing fruit that is not only delicious but also rich in nutrients.