How Tea Is Made

Every true tea, green, white, oolong, black, pu'er, and yellow, comes from a single plant, Camellia sinensis. The leaf you start with is remarkably similar whether it becomes a delicate white tea or a brisk breakfast black. What separates one type from another isn't the plant. It's what happens after the leaf is picked, mainly how far the leaf is allowed to oxidize, and when that oxidation is stopped. That single idea is the key to understanding tea. Once you have it, the rest of the process makes sense.
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One plant,
Six families of tea

Tea is traditionally grouped into six families, arranged roughly by how much the leaf oxidizes. Green tea sits at one end, with no or the lowest oxidation of all. The oxidation process is stopped early by applying heat, leaving a cup that's fresh and vegetal, grassy or nutty. Yellow tea is made much the same way, but with a slow, patient "yellowing" step folded in; the result is mellower and rounder, with less of green tea's grassy edge. White tea is the least handled of all: simply withered and dried, with only a very light, natural oxidation, giving something soft, subtle, and gently sweet.

From there, oxidation climbs. Oolong is partially oxidized, its leaves bruised at the edges and then halted mid-way, which is why the family spans an enormous range from bright and floral to deep and roasted. Black tea goes all the way: rolled hard and fully oxidized into a brisk, malty, robust cup. And dark teas, pu'er chief among them, are post-fermented, aged or microbially fermented after drying, turning earthy and deep, and continuing to evolve over time.

Everything below explains how a fresh leaf is guided into one of these.

Before the harvest: Variety, terroir, and shade

Processing gets the attention, but the leaf's potential is set long before it's picked.

Variety. Two main varieties of the tea plant dominate. Camellia sinensis sinensis is small-leafed, hardy, and cold-tolerant, favored for greens, whites, and more delicate styles. Camellia sinensis assamica is large-leafed and tropical, prized for bold, full-bodied black teas. Within these sit hundreds of cultivars, each bred for flavor, hardiness, or a particular style.

Terroir. Elevation, soil, climate, and the amount of sun, breeze, and mist a garden receives all shape the finished cup, the same reason wine grapes taste of where they're grown. High-elevation, slow-grown leaves tend to be more complex and aromatic.

Shade. Some of the most prized Japanese teas, matcha and gyokuro among them, are grown under shade for several weeks before harvest. Depriving the plant of full sun pushes it to produce more chlorophyll (a deeper green) and more L-theanine, the amino acid behind tea's savory sweetness, while lowering the bitter catechins. Shade is a processing decision made before a single leaf is plucked.

The Craft of Processing

From leaf to finished tea, the process is best understood not as a fixed sequence but as a set of steps a tea maker draws on selectively, choosing which to use, in what order, and how far to push each one. The style of tea being made determines the choices.

It begins with plucking. The finest teas are hand-picked to the classic standard of two leaves and a bud, the tender top growth where flavor concentrates; hand work lets the picker select carefully and avoid bruising, while machine harvesting trades that precision for speed. From there, the leaves are usually withered, spread out to shed moisture until they're soft and pliable, which also starts the internal chemical changes that lay the groundwork for flavor. How much a tea is withered varies widely: white teas rest for a long, slow wither, while green teas may barely wither at all.

The pivotal decision is when, or whether, to stop oxidation. Left exposed to air after the leaf is bruised or rolled, natural enzymes react with oxygen and darken it, building color and flavor. This is an enzymatic reaction — the same browning you see in a cut apple — not fermentation. Applying heat early, by steaming or pan-firing, deactivates those enzymes and keeps the leaf green and fresh. This timing is what sorts the tea families: halt oxidation immediately and you get green tea; let it run partway and you get oolong (often after gently bruising or rolling the leaves); let it finish completely and you get black tea. Rolling and shaping happen along the way, both to release the leaf's oils and to give the finished tea its form — twisted, curled, pressed flat, or rolled into tight balls that open slowly in the pot.

Nearly every tea is then dried with a final application of heat, which halts any remaining activity and lowers moisture enough to keep the tea stable in storage. A few styles add a step of their own: yellow tea gets a slow smothering that mellows its grassy edge, and dark teas like pu'er are exposed after drying to genuine microbial fermentation and aging.

Finally, the leaves are sorted and graded by size — from whole leaf down to the fine fannings used in commercial teabags.

Photograph: SHI Rufei©
Ministry of Culture and Tourism of the People’s Republic of China, 2021

A small white ceramic bowl filled with loose green tea leaves, placed on a gray stone surface next to a white teapot with blue floral decoration.

How each of the six is made

The same leaf takes many different paths. What follows is the essential route for each — but treat these as the shape of the process, not a fixed formula. Every step has regional and stylistic variation, and the same type of tea is often made differently from one country, region, or maker to the next.

Green tea is picked, lightly withered, then fixed early with heat before it can oxidize, and finally dried. It stays unoxidized throughout, which is what keeps it green. The fixing method is where styles diverge most, steaming in Japan, pan-firing in China — along with how the leaf is shaped, from flat-pressed Dragonwell to long twisted greens.

White tea is the simplest of all: withered slowly, then dried, with no fixing and no real rolling. Because the enzymes are never deactivated, a little natural oxidation occurs along the way.

Yellow tea is made much like green, with one patient addition. After fixing, the warm, damp leaves are wrapped and left to rest — a slow smothering, sometimes called sealing — for hours or even days, which mellows green tea's grassy edge into something rounder.

Oolong is the broadest and most varied category in tea. The leaves are withered, then bruised — shaken, tossed, or tumbled so their edges break and begin to oxidize while the centers stay green. Oxidation is halted midway with heat, and the leaf is then rolled, shaped, and often roasted. Because that midpoint can fall anywhere from lightly to heavily oxidized, and because roasting adds another dimension, oolong spans an enormous range, from green and floral to dark and toasted.

Black tea is fully oxidized. It's withered, rolled hard to open the whole leaf, left to darken completely, and then dried. The result is deep and brisk. Style still matters here — orthodox whole-leaf production and regional tradition produce very different cups — but the defining move is letting oxidation run all the way to the end.

Dark tea, of which Pu'er is the best known, takes a finished green-style base and carries it further through genuine microbial fermentation and aging. This happens quickly in ripe (Shu) pu'er, which is pile-fermented over weeks, or slowly in raw (Sheng) pu'er, which is pressed and aged for years.

One leaf, endless variation

A few things are worth carrying with you. That tea is made two broadly different ways — the slow, whole-leaf orthodox approach we use, which draws the most from every leaf, and the fast, shredded CTC method built for mass market teabags. That the craft doesn't stop at the six families: a finished tea can be roasted into hojicha, scented with jasmine petals over successive nights, or blended with roasted rice, herbs, and fruit into something new.

You may have noticed one thing left out: herbal tea. That's deliberate. Everything on this page comes from a single plant, Camellia sinensis — the only plant that makes true tea. Herbal "teas," more accurately called tisanes, are infusions of other plants, roots, dried fruits, flowers, shrubs, and countless more. They're wonderful in their own right, but they follow different rules, carry no true-tea leaf, and are usually naturally caffeine-free. They belong to their own world, with its own vast set of traditions.

And that's the larger point: everything here is only the outline. A single page can't hold the full picture, because there isn't one to hold. Every tea-growing country, region, and maker does things their own way; every step branches into dozens of choices, and every choice into dozens more. The same leaf, in different hands, becomes something unrecognizable. Tea is a vast, deep, and genuinely endless world — one you can keep digging into for a lifetime and still find more. This is simply a door into it. The rest is in the cup.