In this Inside Halton article, Dan Sharp from Davey Canada's Victoria office says fall color may be two weeks behind due to warm temperatures.
Ontario’s fall colours are running about two weeks behind schedule in 2026, with warm El Niño temperatures delaying peak viewing across the province, experts say.
Master arborist Dan Sharp of Davey Tree Expert Co. of Canada says cooler nights — a key trigger for leaf colour change — have been largely absent this fall, aside from some cold nights prompting some frost advisories in late September, which may leave many trees still green as we approach Thanksgiving.
How Could Warm Temperatures Impact Fall Colours?
Sharp said warm October weather could impact fall colours, as lowering temperatures in combination with decreased daylight trigger colour changes in the tree canopy.
“The cold night is a signal to all plants across the board that winter is coming — and that’s been missing,” he said.
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The Davey Tree Expert Company provides research-driven tree services, grounds maintenance and environmental and utility infrastructure consulting for residential, utility, commercial and environmental partners in the U.S. and Canada. Established in 1880 and headquartered in Kent, Ohio, Davey has over 12,000 employees who create and deliver sustainable solutions. Davey continues to grow through expertise with the SEED Campus, its newest commitment to training, research and safety. Become part of the Davey legacy by applying today and join one of the top ten largest employee-owned companies in the U.S.