Border Collies shed about twice a year. The coat loses hair year round but during those times of heaviest shedding a Border Collie loses a great deal of hair. Brushing the hair regularly is recommended, about once per day or at least a few times a week. The hair normally should be long on most parts of the dog. Trimming the legs, belly, and between the paws is a good idea and will help keep the coat clean and the Border Collie looking his or her best.
Long hair in the summer may appear to be hotter then having short hair, but breeders will tell you that the long hair acts as a barrier and actually keeps the dog cooler.