I'd be inclined to get it in the ground now that the soil is starting to warm up. It should do much better in the ground than in a pot - prepare the soil first with lots of organic matter.
Check the buds for scale and aphids, give it a precautionary wash with soapy (not detergent) water.

I agree with Urbanite - put in the ground, prepared previously with well rotted manure or soil conditioning compost, and a handful or three of Growmore or Fish blood and bone mixed into the planting hole.

If it really is H. seemanii, I hope its a sheltered spot - its not entirely hardy, that variety,unlike H. anomala

Thanks guys will get it into the ground asap. Was hoping to plant it against trellis in a pot in a shady sheltered spot. Could I temporarily plant into the ground and when night frosts have gone transplant into a pot as was hoping to grow in a pot against a trellis in the long term?

Oooh, I don't really want to have to say this, but this plant is classed as half hardy, and in a pot, it'll be even more vulnerable than in the ground to cold weather.

Yeah hadn't thought about it like that. Will find it another spot int ground. Back to the drawing board!

No-one told my H. seemannii it's half hardy. I've had it for at least 15 years now, planted in the garden and climbing a telegraph pole

I was a bit suprised at 'half hardy' myself, Andrew - I reckon its H3 rather than half hardy, but to be honest, I'm not at all surprised its doing well in the micro climate you've created, I've seen some of the plants you grow in the ground! Does yours retain its leaves all winter? I'd be interested to know, I'm considering planting one in a small urban garden in a very built up area in Hammersmith, was wondering if it would stay evergreen there.

Bamboo - from memory, I don't think so, but I might be wrong. Sorry not to be more definite.

It is only semi evergreen, so if its up the telegraph pole, I imagine the upper parts certainly don't retain the leaves. Thanks anyway.