I am sorry for this delayed reply to your gardening question. We are transitioning to a new Q&A system and your question was unfortunately lost in the transition. I have discovered it now and hope this reply is not too late to be of help.
The supplies for such a butterfly garden depend entirely on how you design the garden. For example you can use timber to make the rectagonal beds or use no timbers at all but just slanted sided raised beds. If you use landscape timber, most are 8 feet long and so it will take 6 to make a double high bordered bed.
For a great list of butterfly plants check out the following web sites. They can provide more info than I can in this brief reply.
Thanks for the question. Please stop in again soon!
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