An almost universal concern is around potential winter plant damage in this winter weather we’re experiencing.
There Are Two Kinds Of Winter Plant Damage
- Really cold.
- Really warm.
And each has its unique set of problems.
The basic answer is that unless the plant has started growing – the buds swelling for spring – there is little chance of damage from severe winter weather. I’m not saying it won’t happen but fruit trees and the vast majority of shrubs will be just fine.
Real damage can occur if it gets freezing cold after the buds have started to swell and open – then all bets are off. But for now – your garden plants should do just fine in the cold because they should all be dormant.
Ice damage to maple tree Within three years, you couldn’t tell this tree had been severely damaged.
The winter of 2016 has been very warm and here’s the deal.
If shrub leaves have unfolded and you’re starting to see green – and a heavy frost/freeze comes back – those green parts will be “burned”. When the leaf finishes unfurling in the spring, those parts will be dead.
If there is no green showing, then the bud is likely going to be fine.
If bulbs have started growing – and there’s only green shoots showing – no problem. If the buds are starting to open and it freezes – it depends. If the freeze is minor, the bulb will be fine. If the freeze is deep and prolonged, you’ll likely lose the flower.
Self-sowing annuals – if these seeds start to germinate and it refreezes, they’re toast.
Self-sowing perennials – toss a coin. Depends on the temperature and the length of the cold snap.
There’s nothing you can do to stop the damage. No spray, no covering.
Will My Perennials Be Fine?
If you have a big snow cover and ice on top of that, there’s no problem for the vast majority of perennials.
Herbaceous perennials – the ones that die to the ground every fall are snug and well under all that snow and ice.
Woody perennials that stay above ground all winter with no regeneration from the roots, e.g. lavender, are likely to be badly burned/killed by all the very cold weather. I’m not betting the farm on mine surviving.
Evergreen perennials – those that keep leaves evergreen most of the winter (hellebore) will be burned to the ground. No problem – they’ll throw new shoots again in the spring and all will be fine.
Again, as long as they haven’t really started growing, no problem. If they’re only showing shoots, no problem for many tougher perennials.
Some of the more tender types that get hit by early fall frosts (Hosta are a prime suspect here) will not start growing unless it’s really warm (they’re a late starter in my gardens)
But if Hosta do throw shoots and if it does get below freezing again, I’d be covering them up with blankets or straw or dry peat moss or something. Otherwise, those tender shoots will be burned.
You’ll be surprised at how much cold an emerging perennial will tolerate. You may have minor damage but the vast majority will be fine.
Trees and Shrubs
Buds likely fine as above.
All those broken branches are going to require remedial pruning to clean them out and set up a better looking shrub.
Tree pruning the same. Do get somebody who knows what they’re doing with tree pruning.
Prune off all damaged wood as soon as possible and certainly before the sap starts to rise in the spring. This will allow trees to regrow naturally. If they are not pruned properly, you’re going to see water-sprouts emerge from the poor or unpruned areas and this is not a good way to allow a tree to regenerate (weak branches). Get them pruned properly.
Shrubs should be “cleaned up” – all damaged wood removed before the sap starts to rise in them as well. Depending on the extent of the damage, the shrub should be allowed to grow out for one year and then a remedial shaping done the second year to bring it back to the shape you want.
Crab apple tree encased in ice
Pushing the zone
Having said that – if you’re pushing the zone (trying to grow tender plants that are marginally hardy in your geography) then all bets are off.
So growing a tender ‘Granny Smith’ apple in Ontario, Canada this winter should cure you of your adventure. 🙂