It was wet when I arrived in Zanzibar. The sort of wet that turns the surrounding turquoise waters a murky shade of Brighton sea-blue. The short rains' I was told, had gone on longer than expected... Not that the mosquitoes were daunted by the unseasonable weather. So it was with particular attention that I listened to my guide, expound the merits of the Quinine tree.

culture - Zanzibar & Pemba, Tanzania [© 2011 Pulse Africa - pulseafrica.com]    

 "It's known as the 40 Tree" explained Joseph "because it can treat 40 diseases -from stomach problems to blood pressure to bleeding gums". And, of course, malaria. The recipe is simple: boil the leaves and bark for around 35 minutes, until the water turns crimson, and drink thrice daily till cured. Does it work? "Oh yes. I have had it many times!" No matter how damp, no visit to Zanzibar is complete without a trip to its famous spice farms; the source of Zanzibar"s wealth after the demise of the slave trade. Not that Quinine trees can be described as spice, of course - that was just a bonus thrown in to the already dizzying array of aromatic exotica at the government-run Kizimbani spice farm. We could smell it almost before we arrived: that promise of oriental mystique, the quest for which spawned the accidental discoveries of Columbus and other explorers of the Golden Age. Long before spice became common in the kitchen, it was used in ceremonial rites. Incense was burned by Noah in the Old Testament, to propitiate an angry Yahweh; and the Ancient Egyptians even had a Demon-God of Perfume, Shezmou.

From the temple to the apothecary: spice became the staple of medicine and was also called on for its aphrodisiac properties. Variously associated through the ages with sanctity and lust, status and profligacy, one thing was certain: it was a costly commodity. So much so, that one pound of cinnamon would cost a Roman centurion six years wages; and as late as 18th century, spice was still used as a form of bribery within the French legal system. Standing now before a skinny cinnamon tree, I remembered that this unlikely candidate was once considered the most poetic and mystical of spices, first found on the island of Ceylon. As Joseph scraped its orange bark, however, it released its magic - that now-familiar, strong and heady aroma. Chew the bark with cumin, advised Joseph, and it will lower cholesterol. The root, on the other hand, when scraped, smells exactly like Vick, and is similarly used as a decongestant and palliative against flu. Aristotle, way back when, found a social use for cinnamon. Mix it with wine, he advised, to render the wine less intoxicating. I was to learn much about local medicinal lore. Take lemongrass, for instance. Originally from China, the juice from its leaves is rubbed on the skin to deter mosquitoes (not too much, mind: it can burn!). It is also planted in close clumps as a snake deterrent, as the long sticky-edged leaves prevent the reptiles slithering through. Or take black pepper, which hails from the Malabar coast. It grows in little yellow berries that cascade from the leaf of the vine, turn red when ripe, and are then dried to make black or white (the latter with the husk removed) peppercorns. Black pepper, I am told, is ground into porridge to scour the womb of post-natal women. Less alarmingly, it can be chewed whole as a remedy against sea-sickness. Peppercorn as a form of rent, incidentally, survived until the end of the 19th Century. Then there is cardamom, the long, crinkly-leaved import from India which is used (a wink, here) by Muslims to mask the smell of forbidden alcohol. Whereas the value of wild mint lies in its properties against spiritual contamination: make a broom out of it to sweep away the evil spirits when someone dies.

We reach a tree bearing fruits that look like guava. A young boy who had been following us with offerings of baskets and frogs that he had woven from banana leaves, shinned lithely up the trunk to pick one. Split open, the casing revealed a brown nutmeg, surrounded by a crimson, fibrous coating of mace. Nutmeg, I learn has a very idiosyncratic quality: when grated into porridge, it is guaranteed to turn shy women garrulous, so that they virtually talk in tongues. By extension, (in larger doses, perhaps?) it is used as a female aphrodisiac. "But it has the opposite effect on men" warns Joseph. "It sends them to sleep!" Addressing the problem of male impotence, he leads me to a clump of fronds, not dissimilar to a Kentia palm. This, I am told, is ginger - although only its root is used. Known since the time of Galen, the 2nd-Century Greco-Roman doctor, and further promoted by the celebrated 10th-Century Arab physician, Avicenna, for its peculiar "hot and moist" properties, ginger has been used as an aphrodisiac since time immemorial. The recipe Joseph gives me is basic: "grate half a teaspoon of dried root into half a cup of honey, and drink thrice daily". Is it coincidence, I wonder, that one of ginger's culinary uses is as a meat tenderiser? By now, we have arrived in a grove of trees towering almost 20 metres high, which bear Zanzibar's most famous export: Eugenia aromatica, otherwise known as the clove. Like nutmeg, originally filched from the Dutch East India Company in the Moluccas, cloves reached Zanzibar in 1818, where they took seed and flourished - particularly on Zanzibar's little-sister island of Pemba. This is now where some 80% of Zanzibar's cloves hail from, the island reached by a twin-prop plane that skims the Indian Ocean and acres of lush green vegetation.

The cloves, laid out to dry along the roadside in every village, perfume the island's air for miles around. It is the most peculiar-looking plant. The leaves, shaped like tear-drops, have unfriendly triangular spikes on their underside, like mini medieval weapons. The pinkish-yellow bud - several of which grow on one stem - produces the best quality clove. The second quality comes whilst the bud is in flower; and the least desirable, once the flowers have disappeared, and the 'sheath' has turned red. The bud then dries to the familiar prickly brown spike, taking its name from the French clou, for 'nail'. The current uses of clove are multifarious: chewed to alleviate stomach ache, its oil used for toothache, and burnt to keep flies at bay, according to Joseph. It was put to more exotic use in Tang China (to chase off devils), in 11th century India (against smallpox), in medieval Spain (as a prototype deodorant, when mixed with cinnamon and wine) and, more recently, as one of the ingredients of laudanum (an addictive mix of saffron, cinnamon, cloves and opium, stewed in sherry - not too dissimilar from the deodorant). Today, the finest clove oil, from the distillery in Zanzibar Town, will find its way to Europe and beyond, to resurface in the perfume industry. In a town as evocative of faded glory as Zanzibar's beautiful but crumbling Stone Town, the nearby spice farms are a living reminder of the Good Old Days. And "Scents" as Kipling put it "are surer than sounds or sights to make your heartstrings crack". One didn't even mind the rain...

Teresa Levonian Cole travelled with specialist Africa tour operators Pulse Africa (www.pulseafrica.com tel: +44 208 995 5905)

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