For starters, it was the first time I’d ever had a spa treatment in a tree house. Okay, so it wasn’t literally a tree house, but it sure seemed like one, since to get to my treatment room I had to climb up an outside wooden staircase surrounded by flowering plants and towering coconut palms. It was also the first time I had a spa treatment centered around the phases of the moon.

Koh Samui, in the Gulf of Siam, is the third-biggest island in Thailand, and the Four Seasons is the island’s poshest resort. Built on the hillside of a former coconut palm plantation, the resort oozes luxury. Bill Bensley, an eco-sensitive American who started out as a landscape architect, was hired to turn the plantation into a lavish resort. Rather than chop down the trees, he designed the resort around them, and so the coconut palms penetrate roofs, decks and even kitchens, giving the resort its unique feel. The 60 spacious villas, scattered around 856 palms, are tucked among lush tropical foliage. Painted gray to match the palm trunks, each villa boasts an interior space bigger than some private homes, a secluded patio and a private infinity pool.

At the bottom of the twisting road through the palms is a stretch of white-sand beach fronting a private bay. Walking up and down the hill is a guaranteed aerobic experience, but never fear, there are golf carts galore just waiting to buzz guests around the grounds.

There’s something about staying at a lavish resort like Four Seasons Koh Samui that gets me into a spa frame of mind. Surrounded by so much luxury, it seems only fitting that I should treat myself to a little luxury as well. And what is more luxurious than a spa treatment or two? With that in mind, I called for a golf cart to whip me up to the spa’s main building.

An exotically lovely Thai woman who radiated serenity ushered me into the main room, where a décor of warm woods complemented by herbal essence, soft music and fresh flowers created a luxurious and tranquil feel that set the tone for the treatment to come.

Spa treatments here are based on the ancient theory that humans are influenced by the rhythms of the moon and the positions of the signs of the Zodiac, so they are created with the phases of the moon in mind.

It appears that the cliché about people acting crazier during a full moon actually has some basis in fact. Since the energy of the moon affects tides, and man is 80 percent water, the theory is that the same energy that causes tides to ebb and flow affects our moods. Thus treatments during the full moon emphasize harmony and balance, to counteract the feelings of restlessness caused by the power of the full moon. At new moon, when the moon’s pull is not so strong, the recommendation is for treatments geared toward detoxification and change.

The moon was waning during my visit to the spa and, while all the treatments are appropriate during this period, I learned that it’s a particularly good time for water-reducing therapies (like water detox) and deep cleansing and purification (like a sea salt peel).

Unfortunately, I didn’t have enough time for the 150-minute salt peel, detoxifying lemon and algae bath and deep-cleansing massage, so I settled for the 90-minute Siam Fusion — a rejuvenating experience that started with some gentle yoga stretching followed by the application of warm compresses and, as a final treat, a massage — in my treetop haven.

Noo, my spa therapist, met me at the top of my climb. We exchanged traditional bows, and she ushered me into the sitting room. Five of these individual treatment buildings, called salas, are scattered among the palms, each with indoor and outdoor Thai-style massage beds, an outdoor shower and bathtub and a steam room.

I changed into a sparkling white robe and sat on the couch while Noo washed and massaged my feet in warm water scattered with flower petals. Then it was on to the treatment room.

Beside the massage table there was an ev er-so-Asian-looking assortment of natural ingredients. I soon learned that these items infused the compress towels and consisted of ginger root, lemon grass, wild lime, camphor and pandan leaf.

Noo began by gently stretching my arms and legs and then manipulating my neck and pressing various pressure points. About this time I began to drift off. By the time she applied the warm ginger- and citrus-infused compresses, I was well on my way to a nap. Good thing the compresses were followed by a massage, or I’d have been out for the count.

A deep-pressure massage is guaranteed to bring you back to consciousness without undoing the relaxing effects of the rest of the treatment.

Beats me how 90 minutes can go by so fast, but it seemed only a nanosecond had passed between the time I entered the sala and the time I was once again exchanging bows with Noo and drifting — mood enhanced — down the wooden staircase surrounded by swaying palms.

THE SPA AT FOUR SEASONS RESORT KOH SAMUI
219 Moo 5
Angthong, Koh Samui
Surat Thani 84140, Thailand
tel 66 77 243 000
www.fourseasons.com/kohsamui