I think what the label means is "don't expect an annual fruit crop in this climate, but it will still make a very pretty plant".
I've got a kumquat and a locquat outdoors which are both fruiting, though I must stress I bought them with fruit developing (no miracle worker me!)
I've had quite a few off them already - I think that helps them produce more. They've got a fair bit of new growth on them too. I have to keep reminding myself that the skins are edible, it seems quite alien to NOT have to peel citrus type fruit!