One of my ideas for the show is to have Audrey II's vines and appendages designed in the shape of a spiders web. Twoey throughout the show creates a late web of lies that he uses to manipulate Seymore into feeding him. Spiderwebs are also natural and would go well with the plant aspect of his design.
Spiders that build their webs outdoors are your friend. Think of "Charlotte's Web". They will catch and eat the mosquitoes in your yard. Poisonous spiders don't come out in the open. The hide in dark places!