Puerto Rico does not need to be persuaded about linen. The guayabera, the pleated, four-pocket shirt worn untucked across the Spanish-speaking Caribbean, is accepted here at weddings, in offices and at official occasions, and its most formal versions have long been cut in linen. A visitor looking for a linen brand in Puerto Rico is therefore arriving in a place with its own settled opinion on the subject. The useful question is a narrower one: which linen, made how, for a climate that is warm and humid in every month of the year.

The climate comes first because it never leaves. Daytime temperatures on the coast sit somewhere between the mid-twenties and the low thirties throughout the year, the air carries moisture off the Atlantic, and the north-east trade wind is the island's relief. Showers arrive without much notice, particularly from late spring to autumn, and pass. In those conditions a shirt has one job, which is to let the body's heat and moisture out. Linen in humid weather does this by structure. The yarn is firm, the weave is open, and the cloth stands slightly away from the skin instead of lying on it.

Humidity is also where the quality of the fibre shows. Linen spun from long flax fibre gives a smooth, strong yarn that softens with washing and keeps its shape; cloth made from shorter fibre tends to feel rougher and to lose its line sooner. Because a shirt in Puerto Rico is washed after nearly every wearing, the difference becomes apparent within a single stay. PP works chiefly in certified Belgian linen, woven in Belgium from European flax and traceable by certificate. A number of colourways in the collection are natural linen without the mark, and the house names them as linen and nothing more.

PP does not make a guayabera, and it would be wrong to suggest that a house working in Belgian linen could improve on a Caribbean original. What the collection shares with it is the principle: a linen shirt cut to be worn outside the trouser, open at the neck, with room for air. The Vibes Linen Shirt, oversized and shorter in the body, sits naturally untucked and comes in Orchid, Vanille, Dubarry and Dark Blue. The Laos Short Sleeve Linen Shirt is the quieter daily shirt, in a dozen colourways from White and Oyster to Coral Orange and Mint Green. Both are in the men's linen collection, and both close with seashell buttons.

On the island, PP is presented at Four Seasons Resort and Residences Puerto Rico, in Río Grande on the north-east coast, within the resort's boutique. The setting is instructive. The resort lies between a long Atlantic beach and the foothills of El Yunque, the rainforest that keeps this corner of the island green, and the light changes several times a day as cloud comes off the mountain. Colour behaves differently under that sky than under the dry glare of the Gulf, and garments are better judged there than on a screen. The Journal has described the resorts where PP is presented elsewhere.

Old San Juan asks for a little more formality than the beach. The streets are steep and paved in blue-grey cobbles, the houses are painted in strong colour, and in the evening the restaurants and bars of the old city are dressed for. PP Casual Linen Trousers in Oatmeal or Vanille with a Laos Long Sleeve Linen Shirt in Dark Blue is at home there, as is the Monte-Carlo Male in Oyster with its walnut buttons. For women, the Amelia linen dress shirt in Coral Orange or Hibiscus stands up well to those painted walls, and the PP linen blouse in Sky Blue or Lemon is the cooler option for an afternoon on the ramparts, where the wind off the bay lifts the kites on the lawn of El Morro.

The coast east of Río Grande is boat country. Catamarans leave Fajardo for the small cays offshore and for Culebra, and the day is spent in and out of clear, shallow water. PP natural swim shorts go into the water, and the linen shirt stays dry for the sail home. On land, the ladies linen set in Sky Blue, Mint Green or Coral Orange is the easy answer between pool, beach and lunch, and is shown with the rest of the women's linen collection.

Care is simple and worth doing properly in this climate. Wash at 30°C on a gentle cycle, dry flat in moving air and out of direct midday sun, and never put linen away damp. Ironing is a matter of taste; many of the island's own linen shirts are worn with their creases, and nobody has ever thought less of a guayabera for looking lived in by evening.

An island with its own linen tradition is the right place to be particular. Ask where the flax was grown, where the cloth was woven and who made the shirt. A house that can answer all three plainly is worth the attention.

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