Olive Tree Frost Damage

Looking at the local weather station stats, we had a 7 day run of sub 30F nights with the lowest coming in at 21.3F

Of the three main types of olives we have planted -Maurino, Frantoio, and Leccino- the Maurino seems to have been hit the hardest.  It is the slowest growing tree in our grove and has the smallest leaves of the three.  The smaller the tree, maybe a 3 foot diameter, the more damage.  The larger, more full trees have damage  contained to the outer branches.

Frankly I was surprised that it was the Maurino most affected.  The cold tolerance of this tree is notable and I believe this tree is a selection for less warm and sunny climates such as Oregon.

This link to a report from Bill Krueger, the Glenn County Farm Advisor, details freeze damage from two notable cold weather events in 1990 and 2010.  Particularly worrying are defoliation photos from the 2010 event which had a low of 23F, two degrees warmer than this 2013 event.

The take home message from this report is;

• Plant hardy cultivars for your climate
• Reduce Nitrogen after July
• Avoid major pruning in the Fall
• Don't over water after harvest
• Water well in Spring to promote recovery
• Request no temperatures under 32F in your prayers

Frost Tolerance of Eight Cultivars by Barranco, Ruiz, and Gomez-del Campo
University of California, Lessons From a Record Breaking Freeze