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I have about 12 fruit trees (one pear, three peach and the rest are apple). We had an early warm spell which kicked the trees into high gear and they started to blossom. Unfortunately, we had 2 nights this week when the temperature got down to below freezing.

My trees are too big to really cover and while I tried to place a halogen work light on two of them all night, I didn't have any other way of protecting them from frost.

Someone told me that if you get up the next morning and spray the trees with water before the sun hits them that it will prevent damage to the tree/fruit.

Is this true?

Airn5475
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  • See also [this answer](http://gardening.stackexchange.com/a/3732/51) to a very similar question. Depending on what stage your blossoms are at, they may be able to withstand some degree of freezing. – bstpierre Mar 31 '12 at 03:32

1 Answers1

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I think the spraying thing is not after, it's during. The cold will freeze the mist, keeping the air around the trees at (but not below) freezing. See http://www.ehow.com/how_5805520_use-freeze-damage-fruit-trees.html for example which recommends a sprinkler. The "releases heat" thing is kind of an oversimplification, but basically as long as you have any liquid water around, it will keep things at zero. The sap of your tree is not pure water, and therefore freezes somewhat below zero. By having the water freeze instead you stay away from the temps that would damage your plants.

That said, http://www.ehow.com/how-does_5245655_spraying-frost-protect-fruit-freezing_.html is total gibberish since evaporation doesn't generate heat, quite the opposite. There is a better explanation at http://www.gardenguides.com/135830-spray-water-plants-during-frost.html

oranges coated in ice

This is a picture from a blog entry that gives you details from the citrus farmer's point of view.

Kate Gregory
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