Fielding Questions: Can these winter-damaged hedges be saved, pruning shrubs and the best way to transplant rhubarb
Q: I’m sure you’ve been bombarded with winter damage issues, but here is mine: How far can a hedge be cut back and still survive? I’m not sure the variety or age since we weren’t the ones to plant it. The hedge suffered breakage from the heavy snow and, of course, rabbit damage. — Heide Martin, Fargo.
A: Thanks for your great photo that shows what happens as both hedges and singly planted deciduous shrubs age. The branches become old, woody, brittle and bare at the base, and foliage becomes smaller and less lush.
Snow breakage is often worse on these older, brittle shrubs. Rabbits aren’t particularly fussy, as they’ll devour old and new. The good news is the shrubs can be rejuvenated beautifully 99 times out of 100 if the root system is healthy.
Winter damage sometimes does us a favor by forcing us to prune out the old, giving new vigorous shoots an opportunity to form. There’s no other way to make such shrubs look nice again, except with the age-old method of pruning back to 6 inches above ground level and letting the shrubs regrow.
If one is hesitant and prunes back only partway, you still have an old woody shrub, only shorter. Have confidence, as pruning back to 6 inches above soil works beautifully in these situations.
Q: We are planning to put our house on the market this summer and have two ninebark shrubs in front of our house. If we cut them back to 6 inches as you said, how long will it take to grow back nicely? — Joann Abrahamson.
A: Ninebarks, such as the purple-leaved Summer Wine cultivar, become choked with large, woody, bare branches after four or five years and look unsightly during summer, if left unpruned.
The best way to keep them healthy with vigorous young branches and pretty foliage is to prune them every three or four years back to the 6-inch level that rejuvenates unsightly deciduous shrubs so well. If cut back now, ninebarks rebound rapidly to a height of about 3 feet by midsummer. If the ninebarks weren’t terribly unattractive last year, then maybe a cutback by about half might suffice.
But knowing what ninebarks do, if it were my home, I would cut them all the way back now, so they would look fresh and healthy for your upcoming sale. They will be attractive again almost as soon as they begin fresh growth. Good luck!
Q: What is the best time to transplant rhubarb and what is the best procedure? I know someone who will let me get a start from their patch. — Ron Arel, Bemidji, Minn.
A: Rhubarb can be transplanted twice during the year: in fall (September) and spring (April). In spring, transplant early, just as rhubarb leaves are starting to peek out of the soil.
To start your own patch from someone else’s existing rhubarb, you can choose one of two methods. In the first method, use a sharp spade to dig straight down through an outer portion of the existing plant, removing at least a 6-inch diameter chunk, or larger, from the plant’s outer perimeter. Dig deeply, preserving as much of the roots as possible. Leave the remainder of the original plant intact, and fill the excavated part with soil.
The second option is to dig the entire existing plant, divide it into portions, take what you need for your patch, and replant the rest for the owner. Both methods are successful.
Let newly planted rhubarb grow for two seasons before harvesting the third year.
If you have a gardening or lawn care question, email Don Kinzler at ForumGrowingTogether@hotmail.com. All questions will be answered, and those with broad appeal may be published, so please include your name, city and state for appropriate advice.