A Friesian comes from a northern European climate and handles cold better than many owners expect, growing a dense coat that stands up well to frost. Winter trouble for this breed rarely starts with the cold itself. It starts with wet: rain and mud working into the famous feathering, wind cutting through a wet coat, and drinking water that is too cold or frozen for him to take in enough. Manage those three things and most Friesians come through winter in fine shape.
Shelter and the blanketing question
What he needs most is a way out of the wind and rain — a run-in shed, a dry stable, or a thick hedge line — because a dry Friesian in still air is a warm Friesian. Blanketing is a judgment call rather than a default. An unclipped horse in good weight with shelter often needs no blanket at all, and over-blanketing a heavy-coated horse can leave him sweating under the rug, which leaves him colder when the temperature drops. Blanket if he is clipped, older, underweight, or if freezing rain is soaking him to the skin. Whatever you decide, check under the blanket regularly: the long Friesian coat conceals both sweat and weight loss, and neither shows from a distance.
Forage is his central heating
A horse warms himself from the inside out, because digesting fibre in the hindgut generates heat for hours. In a cold snap the most useful thing you can add is hay, offered little and often or free choice for horses that do not gorge, so the furnace never goes out overnight. The longest, coldest stretch is between the evening feed and morning, so a generous late hay feed matters more than an extra rug. Friesians are often easy keepers who gain weight readily, so balance the cold-weather increase against his condition — hands on his ribs weekly, under the coat, rather than judging by eye over all that hair.
The feathering: winter's real Friesian problem
Those long feathers that look so striking in summer become mud traps in winter. Damp, soiled hair lying against the pasterns softens the skin and sets up irritation and scabbing in the folds, a misery that hides completely under the feather until the horse is sore. Resist the urge to wash legs constantly, which strips the skin's protection; instead, let mud dry and brush it out, keep bedding and gateways as dry as you can manage, and part the feather with your fingers every few days to check the skin underneath. Cracked, scabby or hot pasterns, or a horse stamping and biting at his legs, are reasons to call your vet before the skin breaks down further.
Water he will actually drink
Horses drink less in cold weather just when dry hay and cold air raise the stakes for their digestion. Break ice as often as it forms, and if you can warm the water slightly, most horses drink noticeably more. Watch intake rather than assuming: a trough that barely drops on a freezing day is information, and a Friesian going off his hay with reduced droppings in winter deserves a vet call promptly, because gut slowdowns in cold weather escalate.
Winter care is usually shared care, with different family members feeding in the dark before work or school. In KinsLe, Family Sharing lets you give relatives you pick access to his profile, so the relative doing the evening check can open that profile before pulling on boots for the yard.