Honestly, I've had some issues, but at the same time, I've been constantly giving my butterflies to friends, which (for the most part) they in turn give me some back. Even when I'm growing flowers, I try to keep about 5 blooms for people to put butterflies on, and then plant the other 15 plots, and keep rotating there. I think that's the biggest thing though- this is near impossible to do on your own without spending a lot of leaf tickets, but I've got 50 topaz flies at this point, and most of that has stemmed from constantly giving and receiving. I count as I catch, and my catch rate on the topaz ones is only about 20%, so 1 out of every 5; I've planted over 100 reds (focused more on them for the essence rewards, among other things; my garden is usually about 10 reds:5 blues).
So I guess that's my best advice. Jut keep handing out butterflies and people will hopefully give you some in return. I'll happily give you a few if you need a boost.
How could I have ever been so blind?
I was waiting for an indication; It was hard to find.