Asclepias will just eke by in shade, will not bloom and will have less nutritional value for Monarch cats. Buddhlea will not fare well either.
Try growing some nettles or false nettles for the Red Admiral.
If you really want to attract Monarchs, you may want to thin out some of your shade trees to make way for Milkweed and Buddhlea.

Desirai,

I have not grown it, but Poke Milkweed (Asclepias exaltata) is supposed to tolerate partial shade. You might give it a try.

Here is a link that might be useful: Asclepias exaltata

Hi Desirai...how many hours is "almost complete" shade?

Tropical milkweed seems to thrive in partial shade but I'm not sure how happy it would be with less than 4-6 hours of sun.

I am guessing butterfly bush wouldn't grow very well, but you can always experiment. Good luck, Tony

Hi.. umm.. the spot is underneath trees, on the edge of the woods. it gets morning sun, but otherwise it's shade. the area is bare, I wanted to plant something there.

I truly appreciate your concern for Monarchs, which are on the decline. Here are a couple more suggestions:
Try Marsh Milkweed (Asclepias incarnata) on the edge of the treeline. They'll tolerate afternoon shade, as long as they get morning sun.
I would also acquaint my neighbors to growing Asclepias spp
such as Butterfly Weed (A. tuberosa), Marsh milkweed and other ornamental varieties in areas where they may provide more sun.
Surely, they'll fall in love c Monarchs!!
I got a similar campaign going in my neighborhood to combat the Japanese Beetle, and this year I'm giving out seedlings to all my neighbors and friends.
Recent decline in Monarch numbers can be turned around if we reach out to our neighbors and get them involved.

I haven't seen a monarch in years, I'd really like to have some live here

Hi Leafhead,

I've never heard this so I'm curious, why would milkweed grown in shade have less nutritional value?

Milkweed that gets direct sun will naturally make more food thru photosynthesis, and this will make the plants more nutritious. A hungry, light starved host plant of any kind is liable to be a weak source of food.
Plus, most Asclepias spp won't bloom much in shade. I do agree c the Poke Milkweed , which is more shade tolerant than most Asclepias spp. We don't see a lot of that one here in WI., but a few places do carry it.

Although no specific reports have been seen for this species, many, if not all, members of this genus contain toxic resinous,

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