December 2013 Freeze Report Part 1 - Citrus

Although I have only lived here through one complete winter (last year) and the last six weeks of winter in 2012, I guess I was a little shocked by the cold wave that occurred here at the beginning of December.  The weather had been in the mid to high 60's and dry for weeks.  All of a sudden the temperatures began to plummet, and over the period of several days each night was a few degrees colder than the last.  During the middle of it all we had a snowstorm dumping 6 inches on some already unhappy citrus trees.  We ended up having a few nights in the mid-20's, and the added problem of the heavy snow which wrecked havoc on some of my frost covers.

Last year the first frost of the season occurred here on December 15, and the coldest temperature of the winter (a balmy 29 F for about four hours) occurred in early January 2013.  This is one of several differences between the latest arctic blast and the last from January 2013.  Another problem was the magnificent weather that we were having prior to the freeze.  Many of my plants were actively growing and had not hardened off at all.  All the lemon and limes were blooming.

This post will focus on damage to my outdoor citrus trees.  A subsequent post will look at cacti and succulent damage.  As you can see from the photos I have cylinders of no-climb fencing around the citrus planted last March.  I covered the cylinders with Agribon row cover and used clothespins to secure the fabric.  Some of the frost protection went kaput when the snow load and/or wind dislodged portions of the covers.  All in all, and considering the harsh environmental conditions, things worked out fairly well.

'Lisbon' or 'Eureka' lemon partially protected by roof overhang

Moderate damage...'Moro' blood orange

'Cara Cara' navel orange..ouch, but the tree will live.

Hope this one will live...'Tarocco' blood orange.  This tree was previously browsed by deer and was trying to grow out of the deer damage when the cold hit.

'Trovita orange'...no damage at all.

The 'Meyer' lemon turned yellow...

Protected 'Kishu' mandarin...even the unprotected mandarins such as 'Satsuma' sailed through the freeze

Not good...variegated 'Eureka' lemon.  I could actually smell the perfume of the cells rupturing during the freeze.

Here's a pleasant surprise...Australian finger lime with only minor damage

The 'Valencia' oranges still look great.  This is an established tree and it handled the cold well.

This 'Marsh' grapefruit handled the cold just fine too.  The age of the tree and presence of a blue oak canopy overhead helped.

Lost most of the 'Bearss' lime crop, but the tree will be okay.

Not all the citrus had row cover protection.  This 'Oro Blanco' grapefruit did fine uncovered, just a little dieback.

So, how cold did it get here?   It started on 12/4 with a low of 32F, followed by 29F on 12/5.  12/6 brought heavy snow and another night of 29.  Then things got worse... 28F on 12/7, and then the worst night of all, 12/8.  My thermometer in the coldest part of the yard registered 24F briefly at dawn, but other areas were a bit warmer, possibly 2-3 degrees warmer.  According to the Northern California Weather Blog  this was some of the coldest weather seen in West Redding in a long time.  The person who runs the blog lives nearby and he recored a low of 27F in his yard on 12/8.  I think the low ranged from about 24-27 here as we have varying topography and a large area, some protected microclimates and some not.

Losses:  Most of lemon and lime crop ruined.  Two trees may or may not come back - a variegated 'Eureka" lemon and a 'Tarocco' blood orange.  This freeze was bad, but the results bode fairly well for my dream of having a producing citrus orchard here.  As my trees get larger they will become more able to handle this kind of weather, and most winters will not be as bad.  If only the weather had gradually cooled allowing the growth of the trees to harden and shut down this would not have been such a shock.  

Well, despite this it was fun to go out in the snow and track wildlife.