There’s a straight-faced line in a scientific report that innovation in tea making in Japan has a fairly standard timetable: every 400 years. Tea growing is a conservative tradition and many of the great names span centuries of a continued tea growing culture, preserving terrain, methods, skills and standards.

What are clonal teas?

Forward-looking science and history-embedded craft are coming together through clonal teas. This is nothing exotic or new; it is the same “vegetative propagation” that has created so many varieties of apples and roses. Plants are raised from cuttings, generally of a single leaf, specially selected for particular characteristics. The timetable is more a decade than four centuries, and over the past twenty years it’s moved into the mainstream of tea modernization. It is now producing some really interesting new teas of superb quality. It is also likely to be key in addressing climate change.

Clonal teas are worth factoring into your exploration of teas, especially Darjeeling oolongs and whites. You’ll increasingly see a Darjeeling tea described as an AV2 clonal, for instance. (This stands for Ambari Vegetative; Darjeeling clones take their names from the plantation that created them. The high quality B157 is from Bannockburn and P132 from Phoobsering. The elite develop the elite.)

It’s a very long and careful development process before the clonal seedlings are ready for planting and for the bushes to begin to yield crops. There’s a lot of “eye judgement” required to identify candidate individual bushes. Nursing their growth is idiosyncratic and selective. In rooting the plants, for example, it is essential to have them facing in the same direction, preferably west or north. Spring shoots should be cut 2-3 cm above the last harvest pruning mark.

One mother bush may provide just 50-300 healthy cuttings a year. The biogenetics and propagation work at the molecular level; you can’t just cut and replant. This is a very expensive transition, in terms of time, method, skills and management. It is directly analogous to moving a new electronic product from R&D through prototyping and on to production and distribution.

Clonal vs GMO

Clonals select, GMO alters, the composition of the plant. This is a very natural process that bears no resemblance to GMO (genetically modified organisms), a contentious concern across the entire food supply chain. The most socially and environmentally responsible leaders in the tea industry have already made it clear that they oppose GMO. If you check out leading retail sites, you’ll find Statements about adopting the Non-GMO Project Verification formal promises certification.  

That move may overstate the urgency and severity of the issues; GMO is not likely to be applied to tea in general. Tea is not a major cash crop on the scale of soy or corn, and has many highly localized variations in environment, growing characteristics, and uses. It will be impossible for seed producers to control wind-swept dissemination of their products in the ways that Monsanto has become infamous for. Add to this the multi-year lead times in development and there seems little incentive for growers or for any large agribusiness supply company.

That is not the case for the major global tea brands, in terms of their using ingredients added to the base tea. Additives are sure to move towards GMO. Many low price tea bags are made from a derivative of corn starch called PLA and, yes, that is very commonly GMO-based.

The clonal path is GMO-free and seems more likely to become a mainstream in tea innovation. Kenya is an intriguing instance. It exports 96% of its teas. These are very much a low end commodity but comprise a substantial part of the nation’s foreign exchange and employment. With falling prices and cost pressures, government-funded research and development agencies have been constantly looking to improve productivity and quality.

Kenya’s Tea Research Institute has spent 25 years developing and launching a unique clonal, TRFK 301/2, to create a tea that may transform its industry. It commands a price 3-4 times higher than standard black tea leaf. This tea is purple, the pigment that comes from its having been bred to pack the leaf with the antioxidant anthocyanin. This flavonoid is used as a medical supplement and preservative. Purple tea opens up new opportunities across the instant and ready-to-drink tea market, pharmacology and foods. It does have one drawback; it’s unpleasantly undrinkable as a straight tea.

The Darjeeling clonals

Here is one example of very drinkable clonal teas that illustrates the highest levels of tea making enabled by this agritechnology. Darjeeling Castleton estate’s Moonlight White is produced in tiny quantities: just 4 kilograms for the first flush – harvest – of the 2015 season (9 pounds) and 12 kg for the second. Moonlight teas are a style of China’s Yunnan whites. There are now around ten Darjeeling estates using the name, analogous perhaps to Premier Grand Cru on a French wine label.

The tea is made from the clonal variety known by its registered name of AV2. This is being adopted for making all types of tea, from blacks to whites. This Moonlight sells for a very hefty $400 a pound — $2 for the initial cup, though the effective price drops since this beautiful tea can be infused several times. It is noted as being just a little extra “tippy” and bright, adding a bit more fullness without any astringency.

The famed Castleton Moonlight White
The famed Castleton Moonlight White


AV2 is one of around thirty Darjeeling clonals. What stands out as different from other tea growing areas is the role of individual estates in entrepreneurial innovation. The main focus across the global industry has been research organizations, mostly government-directed, creating a range of clonal teas that meet general needs to reduce costs, increase yields and improve farming methods. Japan’s entire national green tea farming was driven by sixty years of systematic development, propagation and diffusion of around eighty cloned cultivars, one of which, Yabukita, occupies over 90% of clonal areas. Those areas grew from five to fifty thousand hectares between 1965 and 2000.  

This is the science side of clonals. They have enabled Japan to produce really excellent teas despite its high land and labor and management costs, as well as maintain quality even though using high levels of mechanization. In many ways, Japan’s tea industry now is its clonal tradition. (It started in the 1930s; the previous tea innovations were fueled by Commander Perry’ black ships opening up trade with the US, 180 years earlier. Obviously, the four hundred year cycle is compressing to a fast century or so.)

The Darjeeling elite gardens highlight the craft side that exploits the science. (Both approaches work in sync, of course. The UPASI institute set up by the Southern India Tea Association is very active in supporting innovation and diffusion in the Nilgiri region where Glendale is one of the world leaders in making the transition to most of its teas being clonals.) For crafting clonals, selectivity is the driver and skills in every aspect of management and farming are the vital base for turning invention of new varieties into market innovation. They aim at meticulously targeting and enhancing or suppressing traits in growth and/or the morphology of the leaf. They demand precise attention to every aspect of introduction and adaptation to the environment.

Many of the most elite Darjeeling producers are producing new white tea variants, often using the AV2 clonal, that appear as minor and subtle, but they pervasively affect leaf hues, textures and tips, nitrogen absorption and pest resistance. They are part of the future of good tea, which in effect depends on the future of the leaf. (Soil restoration and management are the most urgent. They were grossly neglected in the 1980s and many estates went out of business. The new generation of managers is making biodynamic farming the core of restoration and nurturing of the terrain.)

Clonal innovation ensures that Darjeeling, the standard-setter for black tea, will be a player in oolongs. The soil and methods of the top estates add a distinctive nuance to these: the famous soft and slightly sweet “muscatel” flavor. The demands for success are becoming apparent. The Darjeeling oolongs grow at a higher elevation, with a more stable temperature range, and a mix of old China bushes and the clonal ones. The AV2 and complementary varieties are noted for their complexity and aromatic floral notes. Over the past decade, new AV2 teas have won most awards in competitions. One of the recurrent themes in reviews is the surprise factor – AV2 teas are decidedly different, not just better, than comparative ones of very high quality: common adjectives are memorable, mind-blowing, unexpected, bolder and even “budful.”

Should you try clonal teas?

Toned down (and not all reviews are glowing), these add up to AV2 clonal teas are “different.” That’s what makes tea so special: variety and contrast. When the differences in the leaf are homogenized away in growing, harvesting, processing and blending, then the distinctions become artificial elements of packaging, marketing, distribution and pricing. If you look at, say, a tin of blended black Breakfast/Morning/Royal/Afternoon tea, there’s nothing to learn about the leaf: its country or countries of origin, type of harvesting, grade, withering, rolling, blending formula, flavoring, additives, etc. It’s just “tea.”

In the end, what distinguishes the two paths of tea from the bush to your cup – Artisan craft and Agribusiness mass production – is whether the leaf is special to begin with – terrain, growing culture, pedigree – and its characteristics enhanced by its processing, or it is an “ingredient” to make a standardized and reliable product. Clonal teas shift the focus of tea innovation right back to where it all starts: the seedlings. In your own exploration of teas to try, it’s worth looking out for mentions of the clonal variety and checking from the descriptions and reviews if this is adding something different that may translate to special for you.

Today, you may not spot clonal teas that may create that special extra. It’s rather surprising how little coverage of the topic there is in general discussions relevant to yourself in making choices of teas to try. The main – and relevant – coverage is in online materials – blogs, detailed product description and reviews – of individual gardens. Just about every elite estate producer is targeting clonals in its top products. Halmari, Khongea (Assam), Glendale (Nilgiri). Namring, Phuguri, Gopaldhara, Tukvar, Rohini, Castleton, Pootabong, etc., etc. (Darjeeling), Guranse (Nepal), varieties of Tung Ting, Bai Hao (Taiwan)…

There is an emerging profile among tea producers. The global industry faces immense pressures of cost, overcapacity, productivity, soil and land management, and fierce competition in export markets – and those are just today’s challenges. There are two paths to take: mass market and “premiumization” – Agribusiness or Artisan. By and large, the artisan tea tradition has followed the Japan innovation timetable, preserving and evolving the best practices.

That won’t work. The new elite must differentiate the premium nature and value of their teas or be brought down by their high labor costs (and growing shortage of skilled workers), fragmented supply chain integration from bush to cup, biodynamic farming, and sustainable land management. Clonal teas are part of a management shift. Looking over, say, the Castleton Moonlight clonal white, what is striking is that this is old fashioned tea processing, traditional skills, very high labor costs  and low volumes. It’s not the compromise and lowering of quality that has marked the Agribusiness path – machine mulching, inferior leaf, additives, bags and bulk blending – but the old best working with a new best type of leaf.

The experts know this. Gopal Upadhayay, who leads Teabox’s procurement team, and has written a number of posts for Still Steeping, picks out in his short accompanying author profile that he loves a good Darjeeling, “especially a cup made from the AV2 clone.” Enough said. Those of us who have only heard a little or nothing about clonal teas need to do their own “testing” and “research” – selfless sampling in the service of public awareness and education. This author can report a very successful research venture this morning with a Rohini clonal Spring black. Very distinctive, with an unusual light citrus zip. The research will be repeated tomorrow.

The featured banner shows a clonal tea plant from the Nilgiris’ TANTEA estate. Photograph by Mahesh Bhat.

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  1. Hi Eric

    I was referring to the Round Up cross-pollination suits rather than the terminator gene — the point I wanted to make was just that any such monitoring would be impossible in the mountain winds, rain and seasonality.

    Peter Keen

  2. Clonal selection and VP (vegetative propagation) have been used in the East African tea industry for more like 5 decades than the single decade you infer.

    The industry worldwide is in fact moving back to seed – for its inherent hybrid vigor and ability of populations to sustain climate extremes, particularly drought. Tocklai Tea Research Institute (the world’s oldest at 111 years) recommend at split of 50 ; 50 seedling and clonal for a commercial plantation. Biclonal and polyclonal seed is becoming popular to gain the field advantages of both types.

    And BTW tea is insect pollinated and seed baries are routinely planted in isolation to prevent cross pollination.

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