Christmas Fern Is a Tough Cookie

Q: I just noticed my Christmas fern has developed bumps on some of the fronds. Would that be caused by a bug, a fungus, or something else? 

A: Christmas fern is one of the toughest cookies in the woodland landscape. It usually does not suffer from any pest, including deer. One disease that it does get is Taphrina polystichi. It causes bumps similar to the ones you described as well as leaf curl. I feel certain that’s what you’ve got. This disease loves shade and moisture so work to minimize both. 

Trim away any leaves that are affected by the fungus. Use sterilized scissors when trimming to prevent the disease from spreading. If you decide to move it, make sure the fern has good air circulation by spacing it out from other plants as well as walls or corners. If you do these things, the bumps and leaf curl will gradually disappear.