Welcome to our forum, Gary! I've been to Meijer's Garden twice while visiting my best friend (who lives in Cedar Springs.) That place is awesome!
I know how hard it is to get a good butterfly photo in a place like this - did you take this indoors or outdoors? My guess would be indoors because it looks a little more like indoor lighting and you chose f2.8 as your aperture - probably trying to keep the background from getting too much attention.
To my eye, the butterfly is a little bit soft and the one antenna is really out of focus (OOF). Try stopping down next time to f4 or 5.6 and see if you don't get a little more DOF on the butterfly while still leaving the BG blurred.
From a composition standpoint I'd take a good chunk off the left side of the frame, bringing the butterfly more to the left and offsetting him in the overall comp. Another thing to consider would be darkening the lighter areas at the base of the frame below the butterfly so they don't draw the eye away.
Good to have you with us...looking forward to more images!
Glad you got to go. Julie gave great advice. It is really tough to shoot there without using flash as your main light, unless it is really bright. The DOF is always an issue. I usually shoot at least f/8, and many times f/11, to have any chance of getting the whole butterfly in focus. I have had some days, when it was bright, that the flash was just for fill, but most of the times, it becomes the main light. I try to drag the shutter to allow some background detail.