End-of-Summer Shedding: Why Your Dog Blows Coat in August

By Taiza Silva, CatDog Grooming Salon, Lowell MA · 2026-07-30

Quick answer: Shedding is driven by daylight, not temperature. As days get shorter in late August, most double-coated dogs start pushing out the summer undercoat to make room for the winter one. A professional de-shedding treatment removes that loose undercoat in the salon instead of on your floor. Most dogs need one session in late August or September and another in spring.

What is really happening in the coat

Hair follicles run on a cycle: growth, transition, rest and release. Light exposure is the main trigger for that cycle in dogs and cats. In New England, the drop in daylight after the middle of August is sharp enough that many pets begin a heavy release phase weeks before the weather actually cools.

Breeds that blow coat the hardest

Husky, Malamute, Samoyed and other northern breeds. They shed in visible clumps.
German Shepherd, Golden Retriever, Labrador, Bernese Mountain Dog.
Pomeranian, Corgi, Chow Chow and other thick coated small and medium dogs.
Long haired cats such as Maine Coon, Persian and Norwegian Forest.

Poodles, Bichons, Shih Tzus and most doodles do not blow coat, because their hair keeps growing instead of cycling out. They need haircuts and brushing rather than de-shedding.

De-shedding is not the same as shaving

A de-shedding treatment uses a releasing shampoo and conditioner, a high velocity dryer and specific rakes and combs to pull dead undercoat out from the root end while leaving the protective guard hairs in place. Nothing is cut short. Owners typically see a large drop in loose hair at home for four to eight weeks. We explain the full process in does de-shedding really work, and why shaving a double coat backfires.

A simple at-home routine for August and September

Brush three to four times a week with an undercoat rake, not just a slicker on the surface.
Work in sections, from the skin outward, and never brush a dry, dusty coat.
Keep water available and add a vet approved omega 3 if your vet agrees. Coat quality follows nutrition.
Vacuum the resting spots, not just the floor. Most loose hair lands where the dog sleeps.
Book the de-shedding session before Labor Day weekend. Late August is our busiest stretch.

When heavy shedding is a health signal

Seasonal shedding is even across the body and the skin underneath looks normal. See a vet if you notice bald patches, redness, scabs, a strong odor, constant scratching, or hair that comes out in one specific area only. Those point to allergies, parasites, thyroid issues or infection rather than the calendar.

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Frequently asked questions

How long does end-of-summer shedding last?

Usually three to six weeks, starting in late August and running into September or October in Massachusetts. A de-shedding treatment shortens the messy part considerably.

How often should I do a de-shedding treatment?

Twice a year for most double-coated dogs, in spring and late summer. Heavy shedders such as Huskies often do best with a session every eight to ten weeks year round.

Do cats need de-shedding too?

Yes, especially long haired cats. Removing dead undercoat reduces hairballs and prevents the tight mats that form near the hind legs and belly.