Emrys Davies wrote:

I am surprised that no-one has mentioned wind burn. You have some
very good explanations he http://tinyurl.com/lh95h2

Yes, it could be wind burn too, but as the tree only came to me a week
or so ago, I'm not sure of its history.

It looks like I'm best off leaving it in its current pot in a sheltered
corner of the garden until its time to repot.[1] I have the JI No 3
and some small pebbles & grit to mix in for drainage when the time
comes.

I also read somewhere that covering the pot in some bubble wrap will
help protect the tree from frosts.

Thanks to all for the advice. If only I'd stumbled across urg when I
was having tomato problems )

[1] Just a slightly larger and nicer ceramic pot rather than the
plastic one that its in now. I suppose I could just place the current
pot inside the other to make it look nice!

--
Chris