The button fern, also known as the kidney fern, is a small fern with delicate, round leaves that resemble buttons. Its scientific name is Pellaea rotundifolia. The leaves of the button fern are usually bright green and glossy, and they grow in clusters from the center of the plant. This fern is a popular choice for indoor gardening because of its attractive appearance and relatively low maintenance needs. It can grow up to about 12 inches tall and wide, and prefers moderate to bright indirect light and consistently moist soil.