Can you? Yes. Will it hold? That depends: IF the aluminum is really thick, that will help prevent the screws from pulling out IF you use the biggest sheet metal screws possible (biggest in diameter; the aluminum is probably hollow so length won't help) IF what you're hanging isn't too heavy. Then it should work. But proceed with caution! Good luck.
Comes with ordinary screws for wall mounting.
Yes! I use these to hang baskets of petunias and hummingbird feeders. Very sturdy and hold up well mounted outside for several years so far.
You always run the risk of damaging the tree - and this would make very easy access for squirrels who like to steal birdseed
This bracket will hold a hanging basket up to 40 lbs.
has 2 screw holes. Mount in a few minutes. Even use masonry anchors and hung on brick wall