I think it's much too late to feed, and whether you move it to a greenhouse depends on the size of the pot. It wouldn't hurt. I think lagging the pot to protect the roots from the cold might be a good idea in any case. Start feeding next spring.

Thank you Gattina,
I can lift it okay so I think I`ll put it in the greenhouse for the winter once this late sun is done.
Regards Pete.

The size of the pot wasn't really whether or not you could manage to lift it as whether the roots would suffer with only a small amount of soil in a little pot to protect them! Gosh, that sounds awfully condescending, Pete. It wasn't meant to be! It's just that you said you'd only bought it this summer, and I envisaged maybe a 10" plastic pot.....I think you're probably right about the greenhouse, though. My hydrangea is in 20" terracotta, and has been OK for the past couple of years out in the open, but in a sheltered spot under the fig tree.