Lady fern is the one to plant when you want a fern that fills space quickly. Athyrium filix-femina sends up lacy upright fronds in a vase-shaped rosette 24 to 36 inches tall and 12 to 18 inches wide, hardy from Zone 4 through Zone 8 in part shade to full shade, and it settles in faster than most ferns, looking established by the second season.
The fronds are finely cut and light green, softer in texture than the leathery evergreen ferns, and they catch movement in a way that makes a still shade bed feel less static. This is a deciduous fern, so it dies back to the ground after frost and returns in spring.
Native across nearly the whole country, lady fern grows in woodlands, along stream edges, and in damp ditches, which is why it adapts to a wider range of garden conditions than most ferns will accept.
It wants consistent moisture and soil with organic matter in it. Repeated drying is what kills it, so a low spot or a bed you water is a better bet than dry shade under a maple. The fronds get tattered by late summer in exposed sites, and cutting the worst back brings fresh growth. Deer leave it alone.