A few years ago I made a gardener's wreath from an old piece of hosepipe. The outside elements caused the flowers to fade and the wreath to lose its shape. Making a new one has been on my to do list for quite awhile. I've been gathering bits and pieces, some new and some from the old wreath and finally this afternoon I got around to gluing it all together.
Wrap an old hose around about 4 times to form the wreath shape. Tie with twine in a couple of places to hold the shape. Then glue on any garden related items you can find.
I even found an old hosepipe hanger to fasten onto the door and hang my wreath onto. I think the hanger will help the wreath keep its round shape as my old one had been stretched out of shape.
Here is a link that might be useful: gardener's wreaths