In my previous post I explained the different factors that impact how plants might respond to freezing temperatures. Once we have built a foundation of understanding the various factors, we can begin to look at the different types of winter injury.
The most common signs of winter injury in the PNW include:
- Bud/Stem Damage: This can lead to a decrease in flower or fruit production, if severe, or branch dieback.
- Frozen Roots: Especially the case for plants in pots above ground and shallow rooted plants like Rhododendrons.
- Sun/Wind Scald Leaves or Bark: Cold temperatures mixed with heavy winds and bright sun can lead to a sunburn effect on plants, much like the one we saw in June with record breaking heat.
- Bark Splitting and Cankers: Most susceptible on younger trees and typically found at crown/base of tree.
- Leaf Droop/Roll: Typical response from a Rhododendron after a hard freeze, leaves will also start to appear darker in color and may drop.
- Branch Breaking: Typical of hedges or large tree branches that get weighed down from snow or ice.
- Delayed Symptoms: Winter injury can cause a decrease in plant health leading to associated stresses like insect, fungal or virus infestations that will not show for months if not years later.
If we see that any of your plants are experiencing any type of winter injury, we will take the necessary steps to make sure that plant is brought back to good health, such as proper pruning to remove damaged branches and dieback, fertilizing or mulching plant to ensure a proper balance of nutrients and making sure the plant is adequately watered over the summer.
Preparing for extreme weather can be difficult, below are some tips to make sure your landscape is best prepared to handle the stress:
- Plant Selection and Location – Select hardy plant material (preferably native) and plant in the right spot.
- Use windbreaks in planting schemes if site is over-exposed and has heavy winds.
- For plants that are in containers, move to more sheltered locations to protect from elements.
- Keep plants as healthy as possible through the year with proper watering and fertilization, strong plants have easier time overcoming extreme weather.
- Mulching regularly helps keep roots nicely insulated, limits loss of water, and suppresses weed growth.
PLM and our team of managers and designers are here to help.