Dogs should be groomed all year round. Dogs love routine and if kept to a strict schedule, know when its time for their hair cut. My dog happily jumps on the grooming table as soon as we enter the salon. He loves his time with me when its just us and he gets all the attention. most dogs live in centrally heated houses, you can stick to the haircut all year round. If you are worried about the cold when they are out walking, why not get a coat, or encourage more play. My dog loves chasing his ball and he never gets cold.