OK, we all know that as exotic gardening becomes more popular the superstores like B&Q are going to want to cash in on it. Last year I noticed them selling Phoenix Roebelenii as an outdoor palm. They have been doing this for some years now. While these guys can sustain some frost they really do not like it at all. Fleece will help out a little, but take things below -4c and you will have some real trouble. Although they look nice with their light feathery fronds you are well advised to avoid them unless you keep them in a pot and bring them undercover for the Winter.
Now, what's even worse is last year I noticed, to my horror, that B&Q were trying to pass of the very tender Bismarckia Nobilis as a hardy palm !?!?!?!! They were the silver forms (which are the toughest), but they will defoliate at 0c easily !!!! DON'T BE CONNED !!! B&Q were selling these at a HUGE 50 quid each too !!!! It was a complete laugh reading the pointless info cards they stick to their plants... "Needs protection from heavy frosts"... more like needs protection period!