As you probably know (ha!) this is an Asclepias physocarparpa plant (also known as Gomphocarpus physocarpus, commonly balloonplant, balloon cotton-bush or swan plant), a species of milkweed favored by Monarch butterflies.
Question: Are our butterfly plants some sort of milkweed? If yes, what kind? According to this BBG.org story, some milkweeds are great for gardens while others tend to overtake the beds. So I’m wondering what exactly we already have and what we want to get or enhance.
When I went to the Butterfly Conservatory at the Museum of Natural History a few months ago, one of the butterfly handlers advised me to talk to a local nursery to get the best plants for egg laying, as the female monarch is picky. But now that I look into it, it seems like the feeding and egg laying plants are the same– milkweeds. Any thoughts?
Incidentally, a commenter on the BBG story suggests that fennel is a good host food for black swallowtails.
In other news, I’ve updated the website but I’m not sure the bells and whistles have kicked in yet. I’m writing this on the same old interface. -Denise
Concord Village EarthLab 
Here’s an article on using zinnias to attract butterflies. Maybe we have zinnias?
http://www.bbg.org/gardening/article/zinnias_butterflies_will_come
This is great! I have an email out to the office (sent it too late on Friday, I guess, to hear back) about having a garden seedling planting meeting 10-12 noon on Sat Feb 23d in the community room. I’m thinking we really be limited in what we plant — tomatoes, a few eggplants and cucumbers, herbs (mostly basil and dill), and flowers. We definitely add zinnias! I was also thinking we shd do it as a sub-irrigated planter workshop again. We can use the old ones from last year, or people can bring new bottles to reuse . . . The idea would be that everyone just plants a couple of seedlings to bring down to the garden!
We could plant milkweeds outside out beds, perhaps on slide hill, or that little grassy small hill we created at the bottom of slide hill. What do you think? I don’t think our existing plants are milkweed — they are labeled as “butterfly bush” even at the Children’s Garden at the BBG . . . but I’ll see what i can find out . . .
And on fennel, it is — but, as I understand it, it’s same family as dill, carrots, and parsley, which have been doing such a good job of bringing the swallowtail caterpillars to us . . . so maybe we don’t need more?
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