"Well, you're from Yorkshire, aren't you?" said Madeleine, the food editor of this magazine, when she asked me to taste rare, whole-leaf teas from China and Taiwan. Asked for elucidation, Madeleine said that Yorkshire is the greatest stronghold of traditional British tea and "it would be interesting for you to try something different".

"Rarely an hour passes when I'm not wafting a cup of tea with my cloth cap," I replied somewhat sarcastically, but she has a point. My home county is not renowned as the cutting-edge of culinary adventure, particularly where its favourite refreshment is concerned.

But tasting these rarefied infusions was even more of a novelty for me than Madeleine suspected. For the past 28 years, I have lived with a woman who has a violent antipathy to tea. As a result, my life is irrigated by a torrent of Peruvian coffee – maybe six mugs a day.

"You don't!" says Jennifer Wood, co-founder and proselytiser-in-chief for the Canton Tea Company, whose tea I had been dispatched to taste. Deeply shocked, she briskly summarises the health benefits of drinking China tea. "If you got into drinking more tea and less coffee, the tubes going into your heart will be stripped clean and weight will fall off. Tea takes up fluoride for your teeth and gums and reduces cholesterol."

It must be conceded that Jennifer is a walking advertisement for her products. Slender and lively, she simmers with enthusiasm when making our first infusion. This takes the unexpected form of grey, wrinkly little balls. "They're called jasmine pearls," she tells me. To my eye, they look more like winkles. "Watch them unfurl – it's amazing," says Jennifer, as she pours warm water on the tiny, perfect spheres in a glass teapot. It's all a long way from teatime in Yorkshire.

We are seated in a greenhouse. Petersham Nurseries, near Richmond in Surrey, where Skye Gyngell operates a posh lunch destination, also acts as the flagship outlet for the Canton Tea Company. The luxurious nature of our tipple – mellow, almost buttery, with a jasmine bouquet – matches the polished and buffed clientele. Despite its pale gold colour, the tea is unexpectedly satisfying. "Most jasmine tea has been sprayed with 'nature-identical chemicals'," says Jennifer. "The result is sweet, cloying and muddy with an overpowering aftertaste. This tastes of fresh jasmine."

Jasmine tea is a type of white tea. Other varieties sold by Canton Tea – green, oolong, black and pressed bricks of leaves called puerh – reflect varying degrees of oxidation of tea leaves, the same browning you get when you slice an apple. "White silver needle tea is picked by hand. There are just a few days in the year you can pick immature leaves that haven't opened. They are spread on bamboo racks in the sun to dry," says Jennifer, as she pours me a cup. "Do you get melon? It should have notes of sweet honeydew and a creaminess, especially in later infusions."

Jennifer is referring to a major advantage of whole-leaf China tea for the economically-minded. One pot will keep you going throughout the day, as long as you don't allow the leaves to steep. Four or more infusions are feasible with loose leaves and 30 or 40 infusions are possible with puerh. "Though the price of a 50-gram packet might be £7.50, you can get a hundred, even thousands of cups from it," claims Jennifer. "With China teas from some other suppliers, you have to use the first infusion to get rid of the dust, but our teas are not dusty. The first infusion is good and the second and third are even better. I'm surprised at how inexpensive these teas are considering how much work and skill goes into them."

Formerly a copywriter for the late Anita Roddick, Jennifer became obsessed with China tea when her partner brought back packets from trips to the Far East. Tea made from the dried leaves of the evergreen Chinese camellia shrub has been sipped for at least 2,000 years. (The plantations in Assam and Sri Lanka that produce traditional British tea date only from the 19th century.) Jennifer admits that the first four years establishing her company has been hard work. "Knowledge of tea in this country is where wine was 30 years ago when everyone was drinking Blue Nun."

What elevates the Canton Tea Company above other importers is that it has an exclusive buyer based in the tea plantations. Sebastien Leseine is described by Jennifer as "a Monty Python, extreme Frenchman. He can't understand why we might have trouble selling 50 grams of tea for £155". The life of a tea buyer calls for unusual qualities. "He may spend nine or 10 hours a day with a tea master and the food is terrible – soup like dishwater, fibrous vegetables and smashed chicken with the bones mixed in with the flesh – but the tea is fantastic." The Canton Tea Company utilises the services of a fifth-generation tea master called Mr Chen. Steeped in tea, he approaches the topic with mystic intensity and rations his judgements to a dozen words a day.

Fortunately, the UK retailer of his masterly selections is more forthcoming. "This is green tea that has been barely oxidised before being pressed in a hot wok to stop oxidation," says Jennifer. "What flavour do you get from it?"

"A bit of seaweed?"

"I can taste chestnuts and asparagus with a lovely unctuous quality on the palate. It's tasty without any bitterness. Low-grade green tea in tea bags will taste bitter and coarse because it's so dusty. It gives you everything at once like a French tart."

We progress through oolong ("Can you taste apricots from the semi-oxidised leaves?") and black tea ("Caramel-y, cocoa-ish, a bit honeyed") using ever-hotter water in ever-smaller clay teapots known as "little pets" in China. With their incomparable gift for metaphor, the Chinese have an intriguing series of gradations for the bubbles in simmering water: shrimp eyes (70-80C for white tea), crab eyes (80-85C for green tea), fish eyes (85-90C for oolong), rope of pearls (90-95C for black tea) and raging torrent (95-100C for puerh). The flat water produced by a protracted boil is graphically characterised as "old man water".

Our final tasting is puerh made with cooked leaves. After unwrapping a circular brick of tea, Jennifer prises off a small chunk with an implement rather like an oyster knife. The smell instantly reminds me of sniffing my dad's baccy pouch. After splatting the fibrous lump with raging torrent water in the tiny teapot, Jennifer fills a minuscule cup. "At present, I'm getting leather and hay but fruit and flowers will come through with successive infusions," she says, cradling her little pet.

Since my encounter with China teas in Petersham, I have become an ardent convert. I particularly like the low-caffeine white and green types, which is somewhat surprising considering my former addiction to coffee (I am now down to one mug a day). The fact that the leaves suffice for numerous pots of tea is another factor in their favour. After all, I do come from Yorkshire.

For further details visit cantonteaco.com or call 0845 519 5575

10 great places to have tea

By Andrew Connelly

Betty's

Yorkshire institution serving traditional blends and exotic offerings.

1 Parliament St, Harrogate, 01423 814070, bettys.co.uk

Mo Café

Sip mint tea in this Moroccan Aladdin's Cave.

25 Heddon St, London W1, momoresto.com

Yauatcha

Dim sum teahouse featuring tea-infused cocktails.

15-17 Broadwick St, London W1, yauatcha.com

Loopy Lorna's

The décor's as unusual as the 'sparkling Darjeeling' tea.

370-372 Morningside Rd, Edinburgh, loopylornas.com

Boston Tea Party

Popular west country café for loose-leaf devotees.

75 Park St, Bristol, bostonteaparty.co.uk

The Tea Cosy

This shrine to all things royal has house rules and traditional English teas.

3 George St, Brighton, theteacosy.co.uk

The English Tea Room at Brown's Hotel

London's oldest hotel is the place to take piping-hot tea in fine china.

Albemarle St, London W1, brownshotel.com

Teapod

Tea timers help brew your infusion to the millisecond.

31 Shad Thames, London SE1, teapodtea.co.uk

Vintage Emporium

This quirky boutique offers tea and homemade cakes.

14 Bacon St, London E1, vintageemporiumcafe.com

Palm Court at The Langham Hotel

The birthplace of afternoon tea, the five-star Langham makes a decadent cup.