Okuhikari

Okuhikari is a late-budding sencha cultivar bred at the Shizuoka Prefectural Tea Experiment Station from a cross between Yabukita and Shizu-Cy225, a Chinese-origin breeding accession the station held. Where Yabukita is the mid-season reference point, Okuhikari buds five to six days after it, which was the entire point: a cultivar that comes into flush safely after the last hard frosts of spring, and that can be harvested as a second wave once a mid-season Yabukita field has already been picked. It was registered in 1987 and has stayed a minor, largely Shizuoka cultivar since, prized in the prefecture’s mountainous tea districts for its glossy deep-green leaf and a liquor its own breeder rated as excellent on colour, aroma and taste alike.

Lineage

• Yabukita ♀ — the seed parent, contributing the general constitution (and, ultimately, the reference point every trait below is measured against).
• Shizu-Cy225 (静Cy225) ♂ — the pollen parent, a Chinese-origin tea accession maintained at the Shizuoka station; reported elsewhere as tracing to tea trees from Hubei province, though the accession’s own introduction history is not documented in the sources used here.

This is a controlled cross, not a landrace selection: both parents are individually known and the cross was made deliberately, in 1964, rather than found in a seed-grown stand. Okuhikari has itself gone on to become a parent twice over. It is the seed parent of Yumesuruga (ゆめするが), crossed with Yabukita’s pollen in 1986 at the same station and registered in 2012 — a slightly-late, high-vigour cultivar bred specifically for a brighter, greener liquor and a milder, less astringent cup than Yabukita. It is also the seed parent of Shizukaori (しずかおり), crossed with Kuritawase in 1989 and registered in 2015 — an early-ish cultivar (about two days before Yabukita) bred for a floral, sweet aroma. Both descendants were bred at the same Shizuoka station, decades apart, by breeding teams that overlapped with Okuhikari’s own — Nakamura Noriyuki, one of Okuhikari’s four registered breeders, is also a listed author on the Yumesuruga research paper.

History

Okuhikari was crossed in 1964 (Showa 39) at the Shizuoka Prefectural Tea Experiment Station, using Yabukita as the seed parent and the Chinese accession Shizu-Cy225 as the pollen parent. It was carried forward as a distinct breeding line and established — 育成 in the Japanese sources, the point at which a numbered seedling becomes a named candidate cultivar — in fiscal year 1985 (Showa 60), a date given consistently by more than one independently reached source. It was registered on 7 August 1987 (Showa 62) under Plant Variety Protection Act registration number 1387, on an application Shizuoka Prefecture filed on 24 March 1986 (application no. 1857), naming four breeders: Oishi Sadao, Hidaka Tamotsu, Kuranuki Koichi and Nakamura Noriyuki. The breeder’s right ran its eighteen-year term and lapsed on 8 August 2005. MAFF’s own variety-registration database carries that record, and the Shizuoka Tea Industry Council’s cultivar guidebook and the vendor and reference pages agree on the year.

Okuhikari is registered under the Plant Variety Protection Act (品種登録), not as a numbered Cha Norin (茶農林) cultivar. This is worth stating plainly because it is easy to assume otherwise: Shizuoka’s other tea-breeding institution, the national station at Kanaya, produced a run of Cha Norin-numbered releases through the same decades (Kanayamidori as No. 30, Okumidori as No. 32, Meiryoku as No. 35 in 1986), and it would be natural to expect a same-era Shizuoka release to carry a number too. It does not: a full appendix table of all 52 Cha Norin registrations, spanning 1953 to 2003, contains no entry for Okuhikari. It sits instead alongside cultivars developed and registered purely through a prefecture’s own programme rather than the nationally coordinated tea-breeding trial that produced the Cha Norin series.

The name itself was chosen for what the cultivar represented rather than simply what it looked like. According to the breeding station’s own account (reproduced by a Shizuoka retailer), it combines oku — the conventional prefix marking a late-budding cultivar suited to the cooler interior hills — with hikari, “light,” in the sense of kōmyō, a ray of hope: late budding, a deep-green and highly lustrous leaf, and characteristics suited to mountain districts were all read together as a hopeful sign for hillside tea farming specifically.

The variety’s own account of its characteristics — reprinted on O-CHA NET from the monthly magazine Cha, published by the Shizuoka Prefectural Tea Industry Council — is written by Nakamura Noriyuki, one of its four registered breeders, which makes it as close to a primary source as this record has.

Characteristics

Okuhikari buds five to six days later than Yabukita, placing it firmly in the late category. The tree is upright in form, more so even than Yabukita, with somewhat-to-fairly strong vigour. Mature leaves are large, oblong to elliptical, deep green and notably glossy. At harvest the new growth runs to a “heavy-bud” type — fewer, larger shoots rather than many small ones — which growers are advised to counter with pruning that increases bud count; left to its own upright habit, the bush also needs training to spread the stool. Yield is reported as about the same as Yabukita’s.

Its cold tolerance is a genuine step up from Yabukita: stronger resistance to red-scorch cold injury and to split-bark (crack-type) frost damage, and because it buds late in the first place, it tends to miss the spring frost window that catches earlier cultivars. Disease resistance is strong against anthracnose, ring spot (gray blight) and blister blight (mochi disease), but very weak against bacterial shoot blight and red leaf blight — young plantings and untrained, natural-form gardens in particular need careful spray management against the former.

In the cup, the processed leaf rolls into a tight, sword-like needle with a deep green colour and sharp gloss. The liquor is bright and full-bodied, and the Shizuoka Tea Industry Council’s own cultivar guidebook rates it top marks — 上上上 — on colour, aroma and taste alike. The aroma is distinctive and, by every account, clearly not Yabukita’s: vendors reach for citrus and kiwi-fruit notes, herbal or slightly spicy undertones, alongside a fresh, tea-typical top note. Against that strong liquor, the taste runs a little more astringent than the colour would suggest, though growers report this softens in mountain-grown material. That deep, already-saturated leaf colour also makes Okuhikari a poor match for deep steaming (fukamushi) — the station’s own processing notes call it “somewhat unsuited” to it — so it is generally worked as an ordinary-steamed sencha, and also turns up as kamairicha (pan-fired tea). It remains a minor cultivar overall, concentrated in Shizuoka’s mountainous districts, above all the Kawane area, though small plantings are documented as far afield as Asamiya in Shiga and Yame in Fukuoka.