The graceful, green fronds of a healthy fern provide a lush touch to any garden. Some hardy ferns can thrive almost anywhere while less cold-tolerant varieties do best as potted houseplants. Deciduous ferns such as the northern maidenhair (Adiantum pedatum), which is hardy in U.S. Department of Agriculture (USDA) plant hardiness zones 3 through 8, die back each winter outdoors but return in spring. Evergreen ferns, including the Boston fern (Nephrolepis exaltata), which is hardy in USDA zones 10 through 12, sometimes return if their roots survive winter outdoors in a zone colder than their hardiness zones. Determining whether or not a fern is dead requires careful inspection.
Check the state of the fern's fronds in spring when new growth usually begins to appear. Some die-back is normal in winter, even in hardy fern varieties. Look for remaining green fronds or new fronds beginning to emerge from the base of the plant to verify that it's still alive.
Trim off dead fronds with shears that were sterilized in a solution containing one part bleach and nine parts water. Remove all the dead fronds at their base, but avoid cutting into the fleshy root crown from which new fronds emerge. Prune back the fern in late winter before new fronds emerge.
Check the fern's base for the first signs of new frond emergence. Small, often light-colored nubs form at a living fern's base, and they eventually uncurl into new fronds. Depending on soil temperature and weather, new fronds may appear late in the season. Give your fern at least one month to show signs of life before declaring it dead.
Monitor the moisture level in the soil while waiting for the fern to revive. Most ferns require moist but not soggy soil. Ensure the plant's soil receives about 1 inch of water weekly either through rainfall, irrigation or a combination of both. Place mulch around the plant to help retain soil moisture.
Dig up the roots and examine them if the fern still fails to produce new growth. If the roots appear healthy and living, then the fern may need more time to put forth a new flush of fronds. Roots that are either rotten and soft or dry and brittle indicate the fern has died.
Things You Will Need
- Watering device
- Avoid fertilizing a dormant fern. Resume fertilizer applications only after the fern produces new growth.
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