Himemidori

Himemidori is a gyokuro cultivar selected from wild-growing native (zairai) tea trees in the mountains of Yame, Fukuoka, and registered in 1960 as 茶農林23号 (Cha Norin No. 23). It was bred to solve a specific gap: until its release, Yame growers who wanted a shaded gyokuro tea had no purpose-bred cultivar to plant, and were putting ordinary sencha varieties such as Yabukita and Rokuro under cover instead. Fukuoka Prefecture adopted it as a recommended cultivar on the strength of its trial results, and it is still associated with Yame — particularly Hoshino village — dento hon-gyokuro today, though as a minority planting rather than a mainstream one.

Lineage

• Yame Zairai seedling — an individual selection from native, seed-grown tea gardens in the mountainous part of Yame County, not a controlled cross.

Himemidori was pulled from a broad survey rather than picked out as a single standout plant. Between 1929 and 1931, researchers gathered large numbers of tea trees from native gardens in the mountain districts of Obuchi and Kasahara villages, Yame County. Individual selection followed in 1933–35, and the chosen plant was carried forward under the working name Fuku-15 (福-15). Like Yabukita, it therefore has no recorded pollen parent, and — unlike Yabukita — it is not documented as the seed or pollen parent of any later registered cultivar.

History

Selection work began at the Fukuoka Prefectural Agricultural Experiment Station’s Chikugo branch (福岡県農事試験場筑後分場) in 1929, aimed at improving on the Zairai seedlings then in general use around Yame. When Japan’s agricultural research institutions were reorganised in 1950, the programme passed to the newly formed MAFF Kyushu Agricultural Experiment Station (農林省九州農業試験場). A dedicated Tea Breeding Research Laboratory was set up there in 1952, Fuku-15 was fixed as a second-round selection tree in 1953, and formal suitability trials ran from 1955. The work was carried out by Takashi Imai (who had died by the time the registration paper was published), Ichiro Baba and Tadashi Yonemaru, together with the paper’s authors, Hajime Sanai and Shun Amma.

Registration followed in April 1960, as Cha Norin No. 23, formally written up in a June 1961 paper in the Tea Research Report (茶業研究報告, No. 17) titled “A Newly Registered Tea Variety ‘Himemidori’ for Gyokuro.” The paper is explicit about the motive: Fukuoka had no gyokuro cultivar of its own, and growers wanting a shaded tea had been putting sencha cultivars like Yabukita and Rokuro under cover instead. Trial results were good enough that the prefecture took Himemidori up as its recommended cultivar for the purpose.

Propagation was the catch

Himemidori’s one serious agronomic weakness, reported in the same paper, was poor rooting from cuttings — a real problem for a plant that, like almost all Japanese tea cultivars, is propagated clonally rather than from seed. Conventional cuttings rooted at 80% but produced almost nothing worth planting on: roots averaging 0.23cm long, six per cutting, 0.03g total weight. The authors’ fix was an etiolation method — covering the mother plants with matting, black vinyl or rice straw for two to three weeks to blanch new growth, re-exposing it to light for another two to three weeks to green it up, then treating the cuttings with a 0.02% NAA solution. That raised the rooting rate to 98.3%, with roots averaging 3.53cm, 47 per cutting and 2.49g — a difference stark enough that the paper states nursery propagation “must” use the etiolated method, and specifies nitrogen fertiliser for the mother-plant gardens supplying the cuttings.

Characteristics

Himemidori buds at medium timing: first-flush picking under shade fell around 5 May in the original trials, one to two days later than Yabukita picked under the same shading. Growth habit is intermediate, vigour is strong, and both cold and general disease resistance are rated strong — the paper draws a specific contrast with Yabukita’s known weakness to anthracnose, which Himemidori does not share.

The leaf is markedly smaller than Yabukita’s: an oval leaf averaging 7.70cm long and 2.81cm wide (15.5cm² in area), against Yabukita’s 10.44cm by 3.66cm (25.4cm²), and slightly thicker (0.28mm against 0.26mm) with a denser palisade layer beneath the surface. Mature-field yield under shade averaged 280kg/10a across the 1957–59 trials — “medium” in the paper’s own assessment, on a par with the general Zairai population’s 200–300kg/10a — and young-tree establishment, while behind general-purpose sencha cultivars, was far ahead of the older gyokuro cultivars it was bred to replace: nearly double the leaf yield of Kyomidori and Samidori by the third year of plucking.

In the cup, the registration paper describes a small, tightly-formed leaf; a deep green, lustrous colour; the aroma characteristic of Yame tea; a pale yellow-green liquor; and the rich umami taste particular to Yame-grown gyokuro — scoring ahead of Yabukita processed the same way in two of the three years of tasting panels and level with it in the third (96.0 average against 88.9). Modern vendor tastings of Yame Himemidori gyokuro describe a comparable profile in different words: sweet corn and creamed-vegetable notes, a medium-thick, low-bitterness texture, and a lighter, more floral character than heavier, brothier gyokuro styles — consistent with the 1961 description of refinement over power.

That refinement is also its limit. Himemidori was never bred to compete with Yabukita as an all-purpose plant — its early growth and its cutting propagation are both weaker, which is why nursery stock still depends on the etiolation method the 1961 paper describes. It is essentially a specialist: a gyokuro cultivar grown in comparatively small volume around Yame, visible today mostly as a named-cultivar lot within Yame’s traditional hon-gyokuro rather than as a cultivar found nationwide.