I have an Allamanda Blanchetii in a 16" container that I'd planned to grow as a vine up one corner of the balcony. Only thing, it's not growing as I'd like it to, which I suspect could be due to planting in container. I'd like to try to grow it as a shrub/bush now, preferably in a 12" container. Am looking for some advice on whether it's risky to transplant/down-pot and hard prune at the same time. It's about a year and half old, has a single vine around 7 feet long.
17th Feb, '18: Just wanted to update, post-pruning the plant started sprouting new growth just below the cut, and later some more further below on the stem, where I'd hoped it would. To let the plant grow for now, I'm just twining the new growth backwards on it's own bare stem. Once these branches are spent, I'll prune the main stem gradually down, by which time the lower growth should be able to support the plant. Eventually hope to reach the height that's optimum here.