This is arguably our most common local fern, and the reason for that is probably because it thrives in a wide range of conditions. Typically it likes shaded slopes with a little extra moisture, but I've seen them do fine with partial sun where lots of water is available. If you really want to treat one, plant it next to a decaying log. They love that.
 
Fragile ferns are on the small side, perfect for a border or rock garden. They are weakly rhizomatous, meaning they'll spread by sending up fronds a short distance from the main plant. In the winter and very dry weather they go completely dormant. 
 
Pairs well with heartleaf arnica, wilcox penstemon, canada violet, and raceme pussytoes.