My milkweed is not "growing like a weed" (unfortunately)

I'm learning I have to be patient and nature plays a part.  For example, my strongest plants (from original planting in fall 2013) appear to have been "nibbled".  This could end up being a blessing because I've read you're supposed to "pinch" (pluck) the top few leaves to help spur more growth.
But you'll see I've had to take protective measures...

Here is how my two best plants looked prior to the damage...

 

Here is one of the tops off...

 

Here is both of them off...

 

 

And here is my effort to protect them (holding coffee "can" in place with four stakes from an old volleyball set)...

 

Cindy may be right that I'm obsessed.  I really just want to get some plants going and developing good roots.