Changing weather & Impact of Hot Summers
Have you noticed how many dead cedar hedges there are around town? The past two summers have been hot and dry. The lack of rain for months on end is taking its toll, most notably on cedars. Stressed out plants are turning brown, covered in cones, or are outright dead. The varieties Thuja occidentalis ‘Smaragd’ (Emerald cedar) and ‘Pyramidalis’ (Pyramidal cedar) are particularly susceptible, likely because they are not native to our climate. Some properties have mega-hedges grown using ‘Thuja plicata’ (Western Red Cedar) that are still green. Western red cedar is a native plant. Other hedges such as boxwood, yew, English laurel, holly and more may be impacted in future years if our region gets more hot, dry summers. Taking a pro-active approach and ensuring your soil is kept moist (not wet) will help your plants to thrive.
Watering During the Rainy Season
If your hedge is showing signs of drought stress, your options are to replace the hedge with a different type of plant or to install an irrigation system that will consistently water the root zone. Soaker hoses set with a timer do a good job. If the roots are dry, you need to water for long periods until the water percolates through the entire root zone. I recommend doing this during the rainy season while water reservoirs are full, before watering restrictions come into effect. Set your sprinkler to run for two hours at a time. Use a water meter or shovel to see how deeply your watering has penetrated the root zone.
Rain is Not Enough
Rain showers are a deceptively shallow source of watering. A rainfall of 10-20 mm, which is a wet day, only equates to 1-2 cm of accumulated water. If all the water actually makes it into the root zone, 2 cm of percolation won’t provide adequate watering for your hedges. Take a proactive approach to protecting your hedges and get a healthy, green row of hedging plants in return.
Jessica Salvador is a Certified Landscape Horticulturist; Christian Kessner is a Certified Landscape Technician and together they are Co-Owners of Higher Ground Gardens, celebrating over 10 years of service in Dunbar.