when do i plant agapanthus bulbs.

MIght be better to buy a plant at the garden centre, then you know for sure what you're getting (they're just finishing flowering now in the south). Its not clear whether you've actually got "bulbs" already though (they're not bulbs, its a rhizome) - if you have, I'd pot them up as soon as - they don't like to dry out too much, so although you won't see much this year, hopefully they'll grow next year - probably won't flower till at least the year after, though. Some of the varieties are not hardy outside though, so it depends which variety you've got.

always keep them pot bound as this will help produce more flower stems.mine are just flowering now.as bamboo said keep in a frost free place in winter i keep mine under a large fatsia shrub in the garden

~lots of local nurseries seem to be selling flowering plants at a reasonable size and price so at least you know what you are getting.Maybe three small ones in a nice pot and see how that goes?
Well worth growing the darker blue ones as they look stunning.
There are quite a lot online,ebay etc~ try
this nursery who hold the national collection.
agapanthus growers. agapanthus plants. agapanthus photos.
www.pcplants.co.uk/ -
best of luck!
Arlene

Keeping them sheltered is only necessary with the more tender ones - there is one in particular, but two, which are hardy. And I find they do much better in the ground here in London.