Check out the link above. These tomato cages would be great frames for butterfly habitats/growing chambers. Use some parasite proof netting to make a sock that fits the frame, pulling it down over the top and down. Attach a wire inside from plant pot to the top of the frame, with your passionvine growing up the wire. Or, use a stake like Nigel suggests. Make a little panel door on one side for access. Use a round disk (plywood or other) on the bottom, sitting on the ground to attach the netting to with glue gun. Voila! Growing chamber!