Dark twisted Lily Eccentric tea leaves with copper and olive highlights in a pale dish.

Tea and Terps · Episode 2

Energy and Wuyi

Nik and Travis open a nine-year-old rock tea from Wuyi, the mountain whose Bohea filled the chests of the Boston Tea Party, and Nik lays out the forgotten physics of agriculture: three equations that describe the board plant nutrition is played on.

Watch the episode Watch Chapters
  • Nik and Travis
  • Wuyi rock oolong
  • 1:50:16

The cup

Lily Eccentric, a rock tea from a damp ravine

Rock tea, or yancha, comes from the cliffs and gorges of Wuyi Mountain in Fujian, and Nik ranks it with Phoenix oolong as a tea in a league of its own. Lily Eccentric is a Qi Lan from Hui Yuan Keng, a long, deep ravine in the mountain's core where some trees see only a couple of hours of sun a day and mist keeps everything damp and mossy.

The packet was from 2017. A well-made rock tea does not go stale, Nik explains; it concentrates and clarifies, and this one still filled the room with flowers, spice and wet stone nine years on. It is lightly roasted, the opposite end of the spectrum from the full-roast rock teas he saves for winter.

Tea
Lily Eccentric / Qi Lan / 慧苑奇蘭
Origin
Hui Yuan Keng, Wuyi Mountain, Fujian, China, 武夷山・慧苑坑
Style
Wuyi rock oolong
Vintage
2017
Brewing
Gong-fu style, 8 grams of leaf, 100 mL De Hua gaiwan, Suisho-bori seigaiha cup
Source
Tea Hong

What Nik noticed

  • Fresh-cut flowers, like lilies
  • Spice and a hint of fruit
  • Clay, moss and wet rock
  • A mineral, almost metallic edge

Special notes

An aged Qi Lan from Hui Yuan Keng, within Wuyi’s core rock-tea country.

Water poured over Lily Eccentric in Nik's white gaiwan, beside an empty cup, on air in Episode 2
On air in Episode 2, at 8:09
How a rock tea is made
  1. WitheredPlucked, then softened in the sun
  2. TossedBruised at the edges and partly oxidized
  3. Fired and rolledPan heat stops the browning; rolling shapes the leaf
  4. RoastedOver charcoal, rested, then roasted again
  5. RestedOne to three years before it is ready to drink
Two rock teas, two roasts
  1. Light roastgold cup, like Lily Eccentric
  2. Full roastcopper to red, for winter

Nik brewed this tea gongfu style: a lot of leaf, a little water and very short steeps, each one peeling back a different layer of the roast.

Chapter by chapter

Inside the episode

Press any time to play the episode from that moment. While it plays, the chapter you are in lights up.

  1. The cup
  2. Play from 0:17 Welcome backNik welcomes Travis of Lobster Fam Farms and sets up the night's subject, energy.
  3. Play from 1:20 Lily Eccentric and a full-roast cousinTwo rock teas from Tea Hong at opposite ends of the charcoal roast.
  4. Play from 2:22 Nine years old, and not staleWhy a well-made rock tea concentrates rather than fades.
  5. Play from 3:23 Gaiwan and a feather-light cupA heavy gaiwan that holds heat, and a hand-punched Japanese cup that sheds it.
  6. Play from 7:43 Brewing gongfu styleEight grams in 100 milliliters and steeps of a few seconds.
  7. Play from 8:44 The tea of the Boston Tea PartyMost of the chests dumped in Boston Harbor in 1773 were Bohea, the old name for Wuyi tea.
  8. Play from 12:15 Export grade and imitationsStream-side teas made to pass for cliff teas, as an old poem describes.
  9. Play from 13:19 Why rock tea takes yearsWithering, oxidation, firing, rolling, and roasting again and again.
  10. Play from 18:36 Layers in the leafEach steep peels back a different layer of the roast.
  11. Play from 21:03 Wuyi Mountain on the mapA UNESCO World Heritage Site and the small core where the most prized teas grow.
  12. Play from 27:25 Hui Yuan KengLily Eccentric's damp, misty ravine in the mountain's core.
  13. Play from 28:27 Rock bone, flower fragranceThe four-word saying it can take a year of rock tea to understand.
  14. Play from 30:44 Red edges, green heartWhy oolong is processed unevenly, the edges more than the center.
  15. Play from 33:05 How long does tea keep?Most oolongs and pu'er improve with age; bouquet-style Phoenix oolongs go in the fridge.
  16. Play from 34:15 Aged tea and cinnamonA 1983 oolong that tasted of cinnamon raisin bagels, and Nik's hunch about why.
  17. Play from 37:53 Joy, gladness, serenityTravis asks which cup of a session is Nik's favorite.
  18. Play from 41:17 Tasting the placeTeas that taste of a sunny hilltop or a damp pit, and of the wood that fired them.
  19. Play from 48:12 Pu'er nextA question about ripe pu'er, and the teas planned for Episodes 3 and 4.
  20. The forgotten physics of agriculture
  21. Play from 49:12 EnergyNik's caveat before he starts: these are his opinions, offered to be tested.
  22. Play from 50:04 Carbon, the MVPMaking fertilizer since 2014, and carbon as something a grower can feed.
  23. Play from 52:12 The NPK modelSprengel, Liebig, superphosphate, the pH scale and Haber-Bosch.
  24. Play from 53:21 No jet-engine upgradeWhy fertilizer changed so little in the century physics transformed.
  25. Play from 55:34 The chessboardNutrients are the pieces; physics is the board and the rules.
  26. Play from 58:38 Planck and the red photonWorking out the energy of one photon at 680 nanometers.
  27. Play from 1:00:00 Blue light stepped downWhy chlorophyll catches blue light it cannot use at full strength.
  28. Play from 1:02:11 Gibbs and the landscape of workFree energy, and what work is possible.
  29. Play from 1:03:11 Nernst and the movement of chargeMembrane potentials, proton gradients, redox, and a meeting with Einstein.
  30. Play from 1:05:22 Pieces plants makeChelators and anthocyanins as pieces that protect their neighbors.
  31. Play from 1:08:37 Changing the board itselfNik's question, and why he now thinks in terms of energy.
  32. Questions
  33. Play from 1:20:11 Fire is stored sunlightA campfire releases the sun's energy, captured in wood.
  34. Play from 1:23:15 Terra pretaAmazonian dark earths made with charcoal and pottery, fertile for centuries.
  35. Play from 1:37:11 The empty bag still smellsThe 2017 packet's aroma, nine years on.
  36. Play from 1:43:33 Old trees, deeper characterWhy older tea trees develop a depth that younger bushes lack.
  37. Play from 1:49:31 GoodnightThanks to Travis, and until next time.

History

The tea of the Boston Tea Party

In May 1773 Parliament passed the Tea Act, giving the East India Company a monopoly on selling tea to the colonies, which still paid a duty of three pence a pound with no say in Parliament. In December, the Sons of Liberty boarded three ships in Boston Harbor and dumped 342 chests of tea overboard. Of those, 240 were labeled Bohea, the old Western name for Wuyi tea.

Nik doubts that Boston was drinking anything like the rock tea in his cup. Oolong making was still young in Wuyi, the region was experimenting with black tea, and demand already far outran what the cliffs could grow, so stream-side teas from much nearer the ports were made to look like cliff teas. An old poem by a Qing dynasty monk, the Song of Wuyi Tea, describes exactly that.

Last night 3 cargoes of Bohea tea were emptied into the sea. This is the most magnificent movement of all.

John Adams, diary, 17 December 1773, read by Nik
Hear it at 8:44
The chests dumped in Boston Harbor
  • Bohea, the old name for Wuyi tea240 chests
  • All the other teas102 chests

342 chests in all, destroyed on 16 December 1773.

Terroir

Rock bone, flower fragrance

Wuyi Mountain is a UNESCO World Heritage Site, a maze of peaks, cliffs and gorges, and the most prized rock teas come from a small core of it. Lily Eccentric grows in one of those gorges, Hui Yuan Keng, where, as Nik describes it, mist clings to the cliffs and slowly carries water and dissolved minerals down to slow-growing, moss-covered bushes.

Chinese tea drinkers sum up what that place gives the cup in four words: rock bone, flower fragrance, yan gu hua xiang. Nik drank rock tea every day for more than a year before he felt he had an entry-level understanding of it. The best ones, he says, taste of exactly where they grew, whether a sunny hilltop or a damp pit with an hour or two of light.

You could spend a year drinking nothing but rock teas day after day and still not fully understand what those 4 words mean.

Nik
Hear it at 28:27
Generated elevated view into Hui Yuan Keng’s sheltered Danxia basin, with red sandstone cliffs, wooded slopes and small tea gardens.
Original AI-generated elevated landscape reconstruction showing the sheltered valley-and-cliff setting of Hui Yuan Keng; imagined viewpoint, not a mapped exact-source garden.
Light roast and full roast
In the cup Lily Eccentric Full-roast rock tea
Charcoal roastLess: Light More: Deep
LiquorGold Copper, bronze or red
When Nik drinks itSpring and summer Autumn and winter
What leadsFlowers, moss and wet rock Roast, wood and spice

Real structures

The molecules behind the energy story

Five molecules from the episode, rendered from real PubChem geometry rather than drawn. Pick one to read why it matters, then turn it in three dimensions.

ATP

The molecule cells use to carry energy. Light's energy, captured as a proton gradient across a membrane, is stored in ATP's phosphate bonds and spent wherever the plant does work.

Structure data: PubChem open chemistry database

Molecular structure

Drag to rotate. Scroll or use +/- to zoom.

C10H16N5O13P3

Adenosine triphosphate.

A short history

Fertilizer never got its jet-engine upgrade

The way we think about fertilizer was built between the 1820s and 1913: Carl Sprengel's mineral theory, popularized by Justus von Liebig, superphosphate, the pH scale and finally the Haber-Bosch process for making ammonia. Nik calls it the NPK model, and he means it as a compliment. It taught the world that deficiencies limit growth and how to correct them.

In the twentieth century, physics took humanity from gunpowder to the atom and from horses to jet engines, yet fertilizer, in Nik's view, barely changed. Quantum physics, thermodynamics and electrochemistry all describe how plants live, and his argument is that they never fully made it into how fertilizer is designed.

I don't think there's anything wrong with the NPK model, but it is incomplete.

Nik
Hear it at 52:12
How the NPK model was built
  1. 1820sCarl Sprengel sets out mineral nutrition
  2. 1840Justus von Liebig makes it famous
  3. 1842Superphosphate is patented
  4. 1909The pH scale is defined
  5. 1913Haber-Bosch ammonia reaches industrial scale

The chessboard

The pieces, the board and the rules

Nik's way into the physics is a chessboard. Nitrogen, phosphorus, potassium and the rest are the pieces, each with its own moves. The squares are not neutral: properties such as pH and cation exchange capacity change how a piece behaves when it lands, and can lock it up so the plant cannot move it again.

Plants also make pieces of their own and put them on the board: chelators that free stuck nutrients, and pigments and antioxidants that keep the chlorophyll in good positions. Beneath all of it are the rules, and for Nik those are three equations. The NPK model asked which pieces we can move; he wants to ask how the board itself can be worked with.

These 3 equations are the board itself and the rules of the game.

Nik
Hear it at 55:34
Nik's chessboard
  1. The piecesThe nutrients: nitrogen, phosphorus, potassium and the rest
  2. Pieces plants makeChelators, pigments and antioxidants that protect position
  3. The boardThe conditions each square sets, such as pH and CEC
  4. The rulesPlanck, Gibbs and Nernst: light, work and charge

Light, work and charge

Planck, Gibbs and Nernst

Planck's relation gives the energy in a single photon. Nik works it out for red light at 680 nanometers, the color photosystem II's reaction center is tuned to: about 2.9 times ten to the minus nineteen joules, or 1.8 electronvolts. A blue photon carries more, so a blue-excited chlorophyll first sheds the surplus as heat, within a fraction of a trillionth of a second, before its excitation is passed on.

Gibbs free energy describes the landscape of possible work: which reactions can run, and how much useful work they can do. Nernst's equation describes how charge and concentration set a voltage, the language of membrane potentials, proton gradients and redox. Joined, they say the work available from moving charge equals the charge moved times the voltage, the idea Nik keeps returning to. Nernst, by the way, was so eminent in 1910 that his trip to Zurich to meet a little-known physicist helped make that physicist famous: Albert Einstein.

Hear it at 58:38
Energy in one photon
  • Blue, 450 nm2.76 eV
  • Green, 550 nm2.25 eV
  • Red, 680 nm1.82 eV

From Planck's relation, energy equals Planck's constant times the light's frequency. Photosystem II runs on the red photon; bluer light brings more energy than it needs.

Three equations, three questions
Equation What it answers In a leaf
PlanckHow much energy light brings Each photon's energy, by color
GibbsWhat work is possible Which reactions can run, and how far
NernstHow charge behaves Membrane voltages and proton gradients

Moments worth rewinding

Short cuts into the conversation

Moments from the clip archive. Each one plays the full episode from where it starts, and the shorts play on their own.

This tea basically caused the American Revolution

240 of the 342 chests dumped in Boston Harbor were Bohea, the old trader name for Wuyi tea.

Fertilizer never got its jet-engine upgrade

A century of physics transformed nearly everything, Nik argues, except how fertilizer is designed.

  • The whole world wants tea from one small mountain

    The core of Wuyi is tiny and the good leaf is picked once a year, so demand has outrun supply for centuries.

    Hear it at 23:02

  • Why a good oolong gets better with age

    A well-made rock tea holds its roast for years, and makers may roast it again a decade or more later.

    Hear it at 32:54

  • Aged tea and cinnamon

    A 1983 oolong tasted of cinnamon raisin bagels. Nik's hunch is that age peels tea back toward simpler molecules such as cinnamic acid; the chemistry of aged aroma is still being worked out.

    Hear it at 34:15

  • Can you taste the wood that fired the tea?

    Charcoal firing over local woods, guava and lychee among them for Phoenix oolong, leaves its mark in the cup.

    Hear it at 43:34

  • Why photosynthesis runs on red light

    The reaction center is tuned to 680 nanometers; a blue photon's extra energy is shed as heat before its excitation moves on.

    Hear it at 59:43

  • One meeting changed how physics saw Einstein

    In 1910 the great Walther Nernst traveled to Zurich to meet a little-known physicist named Albert Einstein.

    Hear it at 1:04:19

  • A sunscreen that works at light speed

    A pigment needs no metabolism to screen light: the moment a photon meets an anthocyanin, it can be absorbed.

    Hear it at 1:07:01

  • Terra preta

    Amazonian dark earths, built up with charcoal and pottery shards, have stayed fertile for centuries.

    Hear it at 1:23:15

Keep listening

More from the series

Episode 2 widens the carbon story of Episode 1 into energy, and Episode 3 brings it back to the grow.

All episodesThe channel on YouTube