Korean Tea Grades | Ujeon, Sejak, Jungjak & Daejak Explained | KTeaShop
Ujeon, Sejak, Jungjak, Daejak: what Korea’s harvest labels actually mean
Five names, one spring. How Korean law defines each label, where producers use the words differently, and how to choose a grade for a cup, a shelf or a menu.
The short answer
Korean green tea is labelled by when it was picked and how much leaf was taken with the bud. Since the Tea Industry Development and Tea Culture Promotion Act came into force in 2016, its Enforcement Rule defines five labels: Ujeon (before Gogu, around 20 April), Gogu (on Gogu or up to 7 days after), Sejak (8 to 10 days after Gogu), Jungjak (picked in May) and Daejak (picked from June onward).
The standard covers green tea only, and it is a labelling rule, not a quality score. An earlier pick is scarcer and more delicate. It is not automatically the better tea for your purpose.
Last reviewed October 2026 · Written by the KTeaShop tea sommelier team, Zürich
Defined by ordinance, as a labelling standard
The five labels are set out in 차산업 발전 및 차문화 진흥에 관한 법률 시행규칙 [별표 1] 「차의 품질 등의 표시기준」, Annex 1 to the Enforcement Rule of the Tea Industry Development and Tea Culture Promotion Act. Article 10 of the Act lets the Minister of Agriculture, Food and Rural Affairs require tea to be labelled by picking time and leaf condition, and delegates the standard to a Ministry Ordinance (제10조③).
Two limits matter. The annex applies to green tea only (“녹차에 한하여 적용한다”), so it says nothing about black tea, balhyocha or matcha. And it is a labelling standard: it fixes what the words may mean on a package. It does not score the cup, and it does not require every harvest to be graded. Boseong County’s separate quality certification, a sensory panel with an 80-point pass mark, certifies quality; it does not define the labels.
The five labels in one spring
Gogu (곡우, Grain Rain) is the moment the sun reaches 30° of solar longitude, around 20 April. It shifts by about a day from year to year, so every window above moves with it.
| Label | Picking window | Leaf taken | In the cup (typical) |
|---|---|---|---|
| 우전 Ujeon | Before Gogu, read against a normal year’s conditions | 1심2엽, one bud and two leaves | Delicate, sweet, very low astringency |
| 곡우 Gogu | At Gogu, or within 7 days after | 1심2엽, one bud and two leaves | Close to Ujeon, with a little more body |
| 세작 Sejak | 8 to 10 days after Gogu | 1심3엽, one bud and three leaves | Balanced sweetness and umami, clear spring character |
| 중작 Jungjak | Picked in May | 1심3엽, one bud and three leaves | Rounder and fuller |
| 대작 Daejak | Picked from June onward | Not specified | More body and presence |
“In the cup” is a general tendency. Cultivar, processing and the producer change it more than the label does.
Grade by grade
Ujeon 우전
雨前, “before the rain.” The rain is Gogu, the sixth of the twenty-four solar terms. Ujeon is picked in a window a few days wide from bushes that have barely started, which is why it is the scarcest and most expensive label. Read the full Ujeon guide.
Gogu 곡우
The label most English lists leave out. Picked on Gogu or within the following week, to the same bud-and-two-leaves standard as Ujeon. It is the last of the very earliest spring pickings.
Sejak 세작
Picked 8 to 10 days after Gogu, with one bud and three leaves. It still carries spring character, with enough leaf development to hold a consistent profile across a season. For most businesses this is the grade that makes sense. Read the full Sejak guide.
Jungjak 중작
Picked in May, still to a one-bud, three-leaf standard. The leaf has more substance, so the cup is rounder and fuller. Jungjak suits daily service in hotels, restaurants and cafés, and it is an accessible way into Korean green tea on a retail shelf. Read the full Jungjak guide.
Daejak 대작
Picked from June onward, and the only label with no leaf standard. Larger, more mature leaves give more body and the widest supply of the five. Later is not lower quality; it is a different job. Daejak stands up to food, gives tea-based drinks a clear backbone, and works where volume and price stability matter. Read the full Daejak guide.
Three usages you will meet
The ordinance is the layer to lead with, because it is written down and checkable. It is not the only usage in circulation.
- The ordinance. Five labels, each fixed by picking window and leaf count, for green tea only.
- Hadong County. Its published definitions differ: Sejak runs from Gogu to before Ipha (입하, early May), and Daejak is a late-May pick.
- Osulloc. Korea’s largest producer uses Ujeon, Gogu-cha and Ipha-cha as the date axis, and Sejak, Jungjak and Daejak as a leaf-size classification.
So the same word can mean slightly different things on the same shelf. The practical answer is always the same: ask for the pluck date and the leaf standard alongside the grade name.
What actually decides what is in the cup
A harvest label tells you timing and leaf. These tell you more about flavour:
- Cultivar. Seed-grown jaerae-jong (재래종) from Hadong, registered Korean cultivars such as Bohyang and Chamnok, and Japanese cultivars planted on Jeju all sit under “Korean tea.”
- Processing. Most Korean green tea, and Hadong’s in particular, is pan-fired in a cauldron, which pushes it toward roasted, nutty, rounded notes. Steamed tea keeps a more vegetal register.
- Producer and lot. Picking discipline, sorting and firing skill vary from garden to garden.
- The year. Weather moves both the harvest window and the character of each vintage.
- Storage. Green tea is at its brightest when kept cool, dry and sealed.
Choosing a grade
| Label | Supply | Price position | Works best for |
|---|---|---|---|
| Ujeon | Very limited | Highest | Premium retail, gifting, tasting menus, special service |
| Gogu | Limited | High | Premium retail, tasting flights |
| Sejak | Limited, steadier | Upper middle | Specialty tea shops, signature tea service, cafés that brew to order |
| Jungjak | Wider | Middle | Daily service in hotels and restaurants, entry-level retail |
| Daejak | Widest | Lowest | Food pairing, tea-based drinks and mocktails, high-volume service |
For scale: one Boseong producer’s organic line showed roughly an eightfold per-gram spread between its Daejak and its Ujeon in the same season.
Five questions to ask a supplier
- The pluck date. On blends of different pickings, the ordinance requires the latest date to be shown.
- The leaf standard. One bud and two leaves, one bud and three, or unspecified.
- The cultivar. Jaerae-jong, a named Korean cultivar, or a Japanese one.
- Pan-fired or steamed. It changes the cup more than the label does.
- The origin on the label. A single county, a province name, or simply “국내산” (domestic) when leaves from several areas are blended.
Choosing a grade for a business?
Tell the Korean Tea Finder your menu, volume and certification needs, and we will match the grade that fits.
Find your gradeRequest catalogue & samplesTasting for yourself? The Korean Tea Discovery Kit pours Ujeon, Sejak and Daejak side by side.
FAQ
Are Ujeon, Sejak, Jungjak and Daejak official grades?
They are defined labels. Since 2016, Annex 1 to the Enforcement Rule of Korea’s Tea Industry Act sets each one by picking window and leaf count. It is a labelling standard for green tea, not a quality certification.
Is Ujeon always the best Korean green tea?
No. Ujeon is the scarcest and most delicate. A well-made Sejak or Jungjak can be the better choice when you need more body, a steadier supply or a price that works on a menu.
Do these labels apply to black tea, balhyocha or matcha?
No. The annex applies to green tea only. Fermented teas, black tea and powdered tea are described in other ways.
Why do suppliers give different dates for the same grade?
Hadong County and Osulloc use the words differently from the ordinance, and weather moves the harvest each year. Ask for the actual pluck date and leaf standard.
Which grade should a café, restaurant or tea shop buy?
As a starting point: Sejak for a signature or retail tea, Jungjak for daily service, Daejak for food pairing and tea-based drinks. The Korean Tea Finder narrows it down to your menu and volume.