Blueberry – Freeze Protection

Q: The weather in GA is turning sour, and my dwarf peach trees are in full bud, blooms only a few days away. With the temps getting into the mid 20′s this last week of February , is there anything that I can do to protect my peaches?

A: Auburn University says the following temperatures will give 10% and 90% damage to peach fruit, respectively:

First Swell 18 1
Calyx Green 21 5
Calyx Red 23 9
Pink 25 15
Bloom (early) 26 21
Bloom (late) 27 24
Post Bloom 28 25

The calyx is the green “envelope” that surrounds the
bud.

Looks like 26 degrees is your magic number.

see also

Principles of Protecting Fruit from Freezing