Frost Damage? Don’t Prune Yet



Frost-damaged foliage on white-colored Catalina Silverlace (Constancea [Eriophyllum] nevinii).
Note drooping branch-tips and leaves, gray-brown color 1 month after frost event.

Temperatures dipped into the mid-to-low 30’s F. several nights this winter, including one in February.    Some of your sensitive plants may be showing signs of frost damage.   The first sign is often drooping branch tips or leaves that don’t look quite right (see above).  Our white-hairy native sub-shrubs were particularly affected in Mother Nature’s Backyard.  Frosts are not regular events, but they do occur in our warm/temperate area.    We’ll have a complete discussion of cold temperatures and frost next November (2014).

You may be wondering whether to prune out the frost-affected areas now.  Our advice is to wait and see.  In our area, frosts are usually mild.  This means that damage to plants may not be permanent.  In the weeks after a frost, it’s often difficult to determine if damaged foliage will recover.   That’s one reason to resist the temptation to prune out the affected area right away.  If you wait a month or two you’ll be able to tell which areas are recovering (often re-sprouting by spring) and which are truly dead.   You can then prune out the dead branches.

Another reason to wait is to protect the new growth.  Retain the damaged branches/foliage until the new growth beneath has a chance to establish – then prune out what needs to be removed.    If a plant is completely killed by a frost, remove it in spring.  Then consider whether to replace it with a more cold-hardy species – or replant in a more protected area of the garden.