Well, i personally love butterflies and this place was rated as a "must" on my trip to Monteverde. Then, after walking a couple of kilometers from cloud forest reserve, we found the place, that actually turned out to be the garden of a private property. The entrance was super expensive -$12 pp- and the guy at the desk told us that there was a group to come in half an hour so that he wouldn't be able to guide us. well, we said, we can wander around on our own, which was actually what we did.
There are three gardens representing three altitudes that exist in Costa Rica, and in each garden you can find the related species of butterflies.
Though the place was nice and you could see lots of butterflies, i don't think it's worh the money and the effort spent getting there.
If you own or manage Monteverde Butterfly Garden (Jardin de Mariposas), register now for free tools to enhance your listing, attract new reviews, and respond to reviewers.