It survived the winter because of that heating light cable I guess and some extra wintershelter? I had hoped it just survived because of the very sheltered and warm microclimate. Its a pitty you can only grow them with extra heating in winter.
Maybe when they get bigger they get hardier. Then you do not need artificial tricks anymore hopefully. The good thing about that Washingtonia robusta is that its a very fast grower as most palms are not that fast growers. Especially the hardiest ones like Sabal minor and Rhapidophyllum.
Alexander, I hear what you are saying, but this palm is extremely marginal in our climate, and my experience is that leaf damage occurs below -3C. Given that we have had a 1 in 20 year winter, and the temps were very low even in coastal areas, I think Robbin can be forgiven for not experimenting with his beautiful palm. If it was possible I would have fleeced mine in the worst of the weather. If we only have to protect every 10 to 20 years this could be a useful palm for the enthusiast. I can't see it ever being planted as a street or park palm, as the authorities like things to look good most of the time. Mine will look a mess for the next 2 or 3 months.
Although the east side of the UK has the coldest winters traditionally, we seem to be spared the extreme cold that the west can occasionally get. In winter high pressure with no wind we all get low temps. When there is a westerly flow the west has cloud cover and the east clear cold nights, but tempered by the milder direction of the breeze. However, when there is an easterly flow the air is much colder, but the east has cloud cover and onshore breeze which temper the temperatures. In these situations the west has a cold airflow and clear skies. This gives rise to the anomally of my min of -5.6C compared to coastal Cornwall's -7C.
I think in technical terms, perhaps simon and correct me if wrong,
Still clear = Radiation Freeze, east and west fairly equally affected
Westerly flow (mild) West = cloudy no freeze. East = clear, radiation freeze
Easterly flow (cold) West = Clear, advection freeze + radiation freeze. East = Cloudy, advection freeze.
This is a very black and white view and there will be all shades of grey possible as well.