What to do to a garden damaged by ice
Here’s what to do if your garden has suffered damage from ice or freezing cold:
Roses. Notice where new growth emerges. On grafted kinds, if all the growth is coming from below the graft (the swollen bud union just above ground level), the understock will produce only an inferior flower, not the same beauty you bought; dig up the plant and replace it. On ungrafted own-root roses, the basal growth will come true; just prune out the dead canes.
Woody plants. Prune any broken or cracked branches: Cut just above a healthy side branch that is at least one-third the diameter of the damaged limb.
If you can’t tell how much of the branch has frozen, scrape off a pea-size patch of bark with a sharp knife. Just below the bark, the thin layer (called the cambium) will be green if the wood is still healthy, brown if it’s dead. Cut off all dead wood.
If a plant is late in leafing out, wait until at least the first day of summer before you give up on it.