North American Fruit Explorers mailing list at ibiblio

[Hilborn.E@epamail.epa.gov]

Hector wrote: "I had always thought that water by giving off heat when
it freezes, would
protect.  The problem we experienced in the freeze of 2007 April was
that we
turned on the irrigation to protect our blueberries but the temp. went
so
low (into the teens) that the ice was hanging from the bushes and the
sprinklers stopped because of ice accumulation.  What surprised me was
that
the branches froze back - it wasn't just bud damage, but sometimes 6-10
in.
of branch was killed.  This made me wonder if water is only good up to a

certain temp. and then it may do more harm than good.  It seems to have
in
our blueberries.  The bushes with the least water (ice)  were the least
damaged."

I had a related observation during that late freeze.  My Rabbiteye
blueberries were in bloom, and I wanted to protect them.  I only had a
few sheets, so I covered my favorite bushes, left others unprotected.

The bushes that were uncovered were fine.  The bushes that I covered had
damage; any plant part (including branches) that was in contact with a
sheet froze back and died. The sheets themselves had frozen solid during
the night apparently with dew accumulation.

Betsy Hilborn
7a NC