Rain is part of the day on St Lucia. Even in the dry season, from December to May, a shower can roll off the rainforest in the middle of the afternoon, drench the road to Soufrière for a few minutes and pass, leaving the air warmer and heavier than before. A man's wardrobe for the island has to accept that without fuss. Linen takes it in its stride and stays comfortable while it dries.

The island runs north to south, with the busier north around Rodney Bay and Gros Islet, and the steep, green south around Soufrière, where the Pitons rise straight from the sea. A stay often divides between the two, and the road that joins them, winding through banana plantations and fishing villages, takes the better part of two hours. A man's St Lucia wardrobe therefore moves between a marina, a volcano, a rainforest and a resort dinner table, sometimes within one day.

Soufrière, the old French capital on the south-west coast, sits beneath the Pitons, whose volcanic spires and the reefs below them make up a UNESCO World Heritage Site. Close by are the Sulphur Springs, billed as a drive-in volcano, where visitors bathe in warm grey mud pools; the Diamond Falls in their botanical garden; and the cocoa estates on the hills, where the morning drink is cocoa tea. These sights are hot, steep and close together, and they are the part of the trip where what to wear in St Lucia needs the most thought. A Laos Short Sleeve Linen Shirt in Sky Blue with PP linen shorts in White is cool for the estates and the falls; for the mud baths, an old swimsuit is wiser than anything new. The shirts are among the PP linen shirts.

Gros Piton is the climb: a guided trail of a few hours from the village of Fond Gens Libres, steep and rocky near the top, with a view across to Petit Piton and the sea. It is a morning undertaking. Closed shoes, a hat and a shirt that can be sweated in are the whole kit. A Bliss Linen Shirt in Grey, its long sleeves rolled down on the exposed upper stretch, does the job and is still presentable for lunch in Soufrière afterwards.

Between the Pitons, the reef at Anse Chastanet and the bay at Anse des Pitons have clear water, with snorkelling a few strokes from the sand. The PP swim shorts in Black or Oyster belong here, and on a catamaran day down the west coast from Rodney Bay to Soufrière they are worn from the first swim to lunch ashore.

Marigot Bay, a deep, sheltered inlet halfway down the west coast, is where yachts lie at anchor and lunch is taken at the water's edge. A PP Natural Set in White is right there. For the restaurants around Rodney Bay Marina in the north, a Cuba Linen Shirt in Pink or a Male Linen Shirt in Grey with PP Casual Linen Trousers in Black is enough for the evening. What to wear in St Lucia covers the island for men and women together.

On Friday nights the fishing village of Gros Islet closes its streets for a jump-up: grills, rum punch, music from the speakers and the whole village outdoors. Shorts and a shirt with some colour are right; the good shoes stay at the hotel. In October St Lucia celebrates Jounen Kwéyòl, Creole Day, when national dress cut from madras, the bright checked cotton of the old Caribbean, is worn across the island. How that cloth compares with linen is the subject of linen vs madras.

The island's larger resorts dress up a little after dark. Dinner at a hillside restaurant facing the Pitons, with tree frogs calling in the dark, asks for long trousers and a shirt with a collar: a Vibes Linen Shirt in Vanille with PP Casual Linen Trousers in Sapphire Blue, and leather sandals or loafers. One long-sleeved shirt is worth packing in any month, for the mountain and for the mosquitoes of the evening; the reasons linen suits the island's damp air are in linen in humid weather. In the Caribbean, the PP collection can be tried on at the boutique of Four Seasons Resort and Residences, Río Grande, Puerto Rico.

The hurricane season runs from June to November, the months when the island is at its greenest. The dry months from December are the busiest at the resorts and the favoured season for sailing the west coast.

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