Troubleshooting
Forked Spleenwort problems — and how to fix them
Forked Spleenwort (Asplenium septentrionale) is generally low-drama, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Crown rot from poor drainage
The greatest cultivation risk; the crown will rot if the substrate stays wet in winter — use a very gritty mix, ensure container drainage holes are unobstructed, and keep in a sheltered spot during prolonged wet winters.
Vine weevil larvae
The compact root system of small crevice ferns is particularly vulnerable to vine weevil grub damage; apply Steinernema kraussei nematodes in early autumn when soil temperature is above 5°C.
Prevent forked spleenwort problems before they start
Most forked spleenwort issues are care-mismatch, not bad luck. Dial in the basics:
Forked Spleenwort problems — FAQ
Why is my forked spleenwort crown rot from poor drainage?
The greatest cultivation risk; the crown will rot if the substrate stays wet in winter — use a very gritty mix, ensure container drainage holes are unobstructed, and keep in a sheltered spot during prolonged wet winters.
Why is my forked spleenwort vine weevil larvae?
The compact root system of small crevice ferns is particularly vulnerable to vine weevil grub damage; apply Steinernema kraussei nematodes in early autumn when soil temperature is above 5°C.