With their delicate fronds reaching out and their tropical feel, one would think it would be difficult to grow ferns in our climate, but that is not the case. These ancient plants are tough and serve gardeners from the tropics to central Canada as a go-to plant for difficult locations.
While tolerant of some sun, they can form dense colonies in shady areas, filling in where few plants can thrive.
Being in a large diverse plant family provides a wide range of plant heights, textures and even hues. From a practical standpoint, they work well in shady backgrounds in gardens, with a controlled spread that rarely gets invasive. In our climate, they range in height from a couple of inches to about 4 feet, making them useful in a variety of garden situations, from privacy screening to creating delicate gardens among rocks or woodland flowers.
Most are unaffected by black walnut trees and can handle boggy soil with ease. In addition to their tolerance, the wide range of textures and structures can give a gardener an array of choices for garden design. Some ferns are strongly upright and vase-like, while others can float over the ground with soft arching branches.
Other features add interest such as the Japanese painted ferns (Athyrium niponicum) that lend a silvery hue to a shade garden, and cinnamon ferns (Osmunda cinnamomea) that leave interesting brown spikes for winter interest.
While tolerant of most conditions, they generally prefer shade to part sun, with slightly wetter soil. Fertilization is not really needed, but they will respond well if given a bit of balanced fertilizer.
Ferns are generally grouped into those that tend to form clumps, and those that creep. Most people are familiar with the crown type, where green branches emanate from a central crown in a dramatic unfurling. These ferns commonly reproduce via spores that hang to the underside of fronds borne in summer.
As leaves fade, the spores contact the ground and set seed for the next generation. In this manner, the plants perfectly space themselves, while still filling in an area effectively. Other ferns, such as the Christmas fern (Polystichum acrostichoides), grow via rhizomes in a slow, clumping manner.
Regardless of the tough shade garden situation, there most likely is a fern to fit the need. Once you look past the lack of showy flowers, the beauty and usefulness of this plant family will stand out in any backyard setting.
• Jim Stendler is a University of Illinois Extension Kane County master gardener. Email the extension office at email@example.com for more information.