How does everyone in cold areas protect their citrus from Siberian blast freezes?

When the cold air mass is native to Siberia expect bone chilling cold everytime! If it is native to nothern Canada and takes a round about path south, the freeze will be moderate. It is important to know what type of arctic air mass you are fighting against because there is a difference. The 1899, 1934, 1962, 1983, and 1989 freezes came from Siberia and traveled across or near the pole and straight down through Canada to the southeastern United states due to high pressure blockage over Greenland. When the path is round about from Canada, which happens most often, the air mass will moderate significantly and only a light or moderate freeze will result.


In the past I covered with plastic and used christmass lights and sometimes heaters. I decided to switch to frost cloth because it seems to insulate better than plastic and without the greenhouse effect during the daylight hours. There are many potential heat sources that might be effective depending on the air temperature. The most effective would a heater but might be overkill even in severe freezes and there is danger the heater could tip over. Christmas lights seem to work well and distribute heat efficiently, but I am thinking of trying a few heat mats that radiate heat and maintain constant temperature even down to -40F. Each heat mate is 4 feet long 5 feet wide and has a surface temperature from 80F to 130F. There are also outdoor bucket warmers that will maintain water temperature inside to 105F even with air tempatures as low as -40F.

The heat mats are interesting because they have large surface area and maintain a constant temperature even with extreme low air tempatures unlike lights. They will also prevent the ground from freezing.

There was no severe freeze this winter and it has been mild so far but still two weeks before the sun moves north of the equator.

I just use a wooden frame and blankets (with plastic on top if precipitation is forecasted) to completely cover smaller trees and run a 100 watt light to keep them warm inside. For larger trees that are too big to practically cover, I just use this method: Link and hope for the best.

http://citrus.forumup.org/about4975-.html&highlight=

When you bank your plants to protect against severe cold, do you apply fungicide to control foot rot?

nope

I bank with a couple bags of composted cow manure (in the bag). I also cover with sheets --add buckets of water--and use lights where possible.

I do not add fungicide, either. However, I do not leave soil banks up for long periods of times, only to make it through the occasional severe freezes. If that means that I have to soil bank more than once in one year, so be it (though I have only needed to once in the last 5 years).

There are outdoor heat mats with thermostat that should be effective preventing cold injury. The PowerBlanket heat mat with termostat can maintain a temperature of 105 F even with the air temperature at -10 F. You can wrap this around the trunk or place under a cover and increase the air temperature around the plant.



Probably overkill because the temperatures rarely drop much below 24F here, although if you live in a colder climate outdoor heat mats could be much better and safer.