When walking in the woodland area of the Native Plant Garden this time of year, you will meet up with the native fern Polystichum acrostichoides, commonly known as the Christmas fern. These ferns can form large, one- to two-foot clumps; are easy to grow; and are standouts in winter due to their evergreen leaves.
The individual leaves on each frond are stocking-shaped, reminiscent of Christmas stockings, which some people claim is the origin of the plant’s common name. But, in fact, the name “Christmas” fern comes from its having deep green fronds at Christmas time, says NYBG fern expert Robbin C. Moran.
Dr. Moran’s entertaining and enlightening book, A Natural History of Ferns, (available in the NYBG shop or by print-on-demand from Timber Press), explains how these amazing plants reproduce by actually “shooting” their very tiny spores. “The spores leap more than an inch into the air and arch downward,” Moran observes. “It is like watching popcorn popping.”
An inflorescence of Virginia bluebells showing the pink buds that become blue just before opening.
The leaves of Virginia bluebell sprout each spring in such deep shades of purple that they are difficult to see against the dark soil. As the leaves mature, the purple coloration is gradually lost until they become a soft green. Flowers, too, undergo a color change, from pink in bud to a lovely shade of blue shortly before the buds open.
The floral color change is not uncommon in members of this family, the Boraginaceae (borage family). Its members include forget-me-not (Myosotis spp.), viper’s bugloss (Echium vulgare), and lungwort (Pulmonaria spp.), all of which have pink buds opening as blue flowers. The color change is due to changes in the pH of the cell sap, and, like some hydrangeas, plants growing in more acidic soils will have flowers of a deeper shade of blue. Members of the borage family also share in common the shape of their inflorescence, referred to as a scorpioid cyme for the way it uncoils like a scorpion’s tail. A true spring ephemeral, the leaves of Virginia bluebells turn yellow soon after the flowers have finished blooming and are gone by late June.
