My palm-ish tree last year was made of paper. I'm too poor to buy.
I took brown paper and curled it up like a trunk. Then I made green leaves shaped like palm leaves. Simple, flat on bottom and curved on top with one side at a higher curve than the other. Ten I stapled two or three leaves to the BB flat. I took the few remaining leaves, bent them at the base (where they would touch the BB) and then stapled them so they stuck out. So my tree had a few leaves flat against the wall and then about 3 or four sticking out to make the 3D effect, along with the trunk.