What to look for in branches and blossom
Look at the branch, not the flowers
On a blossom branch the wood is most of what you see. It should taper from base to tip, change direction a few times, and show nodes where side shoots leave it. A smooth dowel wrapped in brown tape is the common shortcut and it is obvious at any distance, because real branches are never the same width twice.
Blossom comes at several stages at once
A real branch in flower carries open blossom, tight pink buds and bare stretches all on the same length. Every flower open and evenly spaced along the whole branch is the giveaway. The bare sections matter as much as the flowers — they are what stops it reading as a garland.
Check the length is usable
These are floor-vase and tall-jug pieces, often a metre or more. Longer is not automatically better: measure the vase first, and check the description says the stem is wired, because a branch you cannot bend or trim is a branch you have to build the whole room around.