The centre
Every oolong region has a centre, and the centre is far smaller than the name on the packet suggests.
In Wuyi it is zheng yan（正岩）, the rocky ground inside the park, and it covers well under 100 square kilometres.
Outside it lies ban yan（半岩）, and beyond that the sand and river soil locals call zhou cha（洲茶）.
Those are three grades of ground rather than three places, and the leaf from them is measurably different.
In Anxi the centre is a cluster of townships near the county seat rather than the county as a whole.
In Fenghuang it is Wudong, the eastern peak above 1,000 m where the named old bushes stand.
In Taiwan the centre is Alishan and the higher gardens above it, not the island in general.
Four centres, each one narrow, and each one selling far more tea than it can grow.
Centre here means ground and reputation rather than anything an official boundary map would show.
Buyers are sold the region and assume they are buying the centre inside it.
That gap is the most reliable way to overpay in this whole category.
Find out where the line falls before you spend money on a name.
Why the centre leads
Soil is the explanation sellers give, and in Wuyi part of it happens to be true.
Rocky ground drains fast, holds heat through the night, and gives the tea a mineral note heavy soil cannot.
Skill concentration probably matters more, because the best makers work where the money is.
Roasting takes years to learn, and it sits with families who have fired leaf for generations.
Cultivar is the third reason, since the centre holds bushes that were selected on that ground.
A Wuyi cultivar planted outside the park does not give the same cup, and nobody in the trade pretends otherwise.
Reputation then feeds on itself, because a famous centre draws buyers who will pay for the name alone.
Higher prices pay for better picking, and better picking makes the tea better still.
Trade access helped early on, since the centres were the places with roads, buyers and credit.
Land inside a centre now costs 5 to 10 times what land just outside it does.
That cost is priced into the tea, and it is part of what a buyer is paying for.
Soil, skill, cultivar and reputation, with reputation now the strongest of the four.
What surrounding areas do well
Surrounding areas grow the majority of the tea sold in this category, and much of it is genuinely good.
The gap in price is wide, and the gap in quality is often narrow.
Fujian produces more oolong outside Wuyi and Anxi than inside them, and most of it is sold without a region.
Unnamed is not the same as poor, and a great deal of it is honest everyday tea.
Guangdong outside Chaozhou turns out competent dancong styles from younger bushes.
Younger bushes give a lighter cup, and at 1⁄3 of the price that is a fair trade.
Vietnam and Thailand grow oolong in the Taiwanese style now, and the best of it is clean and sweet.
What those places do badly is the thing the centre is famous for, which is depth and length.
A high mountain Taiwanese tea carries a thickness that a lowland copy never quite reaches.
For a tea you drink while working, that missing depth barely registers.
With a tea you sit down with, it is the entire reason for buying it.
Decide which of those two you are shopping for before you read a label.
A buying note
Pay for the centre once you know what the centre tastes like, and not before.
Learn it first from a seller you trust, then keep it as the reference for everything else.
With Wuyi, buy on roast level and cleanliness before you buy on the ground the leaf came from.
A badly roasted zheng yan tea is worse than a well made one from the outer zone.
With Anxi, compare the modern green style against the traditional one before worrying about townships.
With Fenghuang, a named bush is an unverifiable claim, so treat it as a description of flavour.
With Taiwan, insist on the garden and the harvest date, since those two can at least be checked.
Brew 5 grams in a 100 ml vessel at about 95 °C and steep the first infusion for 30 seconds.
Judge a centre tea on length, meaning how long it keeps giving past the 3rd infusion.
Surrounding tea tends to peak earlier and finish sooner, which is the honest way to separate them.
Ignore any centre claim at a price that cannot support it, because centre ground is expensive to farm.
A cheap zheng yan is not a bargain, it is tea from somewhere else wearing the name.