Lush Caves

Green underground. Lush caves grow moss over the floor and ceiling, hang cave vines with glow berries for light, spread dripleaf over clay pools and drop azalea roots through the roof.

Almost none of that grows anywhere else: azalea, dripleaf, cave vines, moss carpet, spore blossoms, hanging roots and rooted dirt are this biome and no other. Axolotls spawn in the pools and nowhere else in the game, tropical fish swim with them at depths they keep to nowhere else, and glow squid drift through. If you see an azalea tree on the surface, dig straight down: there is one underneath.

The game files it at temperature 0.5 with 0.5 humidity, a mild temperate climate with rainfall rather than snow, though no weather gets this far under. minecraft:lush_caves is an uncommon underground biome from 1.18, and 1.21 still hides it below the trees.

Underground in the Overworld, but with a marker up in the daylight. Dripstone Caves and underground cave systems are what it borders below.

A surface azalea bush or azalea tree marks lush caves directly below; dig down beneath one to reach the cavern.

Uncommon, and the one cave biome you can locate without entering a cave, because an azalea grows above every single one. Dig beside that bush rather than under it: glow berries hang over open water with axolotls in it. No portal is needed, and that bush commonly means one is close: enough to dig for, and most people cross a lush cave while travelling underground for reasons of their own.

Three animals, all of them in the water, and all three fill their spawn slot outright. Axolotls come four to six at a time, glow squid the same, and tropical fish in shoals of eight.

The axolotl is what makes this biome special: it spawns here and almost nowhere else in the game, it fights hostile aquatic mobs alongside you, and it plays dead when it is badly hurt so that it can heal. That makes a bucket of them the closest thing to an underwater pet the game has.

Glow squid drop glow ink sacs, which is how sign text is made to glow in the dark, and the tropical fish add their thousands of colour patterns to a cave that is already the brightest one underground. Per spawn attempt the axolotl is all of the axolotls, four to six at a time, which is a strange sentence until you meet the glow squid on the same count. The quiet residents here are worth a bucket: an axolotl, for example, fights hostile aquatic mobs alongside the player, and this is the biome to visit if you mean to find one. Cod give bone meal elsewhere; down here the meal is what the axolotl hunts, and then the water goes quiet again. Visit if you want one in a bucket.

Axolotl

Glow Squid

Tropical Fish

Thirteen blocks generate here and in no other biome, which is more than any other page on this site: Azalea and Flowering Azalea with their leaves, Big and Small Dripleaf, Cave Vines and their plant, Moss Carpet, Rooted Dirt, Hanging Roots and Spore Blossom. Moss Block and Glow Berries come off the same walls.

The berries here are Glow Berries rather than sweet berries, and they are worth more than food: a cave vine is a light source you can farm. The azalea is the only wood from its trees you will ever cut underground, and it doubles as a marker, because an azalea tree on the surface means lush caves directly below it.

Clay is laid into this floor twice, once as the ordinary pockets and once again as the pools this biome puts down for itself, so a lush cave is a clay mine with a garden over it. Spore blossoms hang from the ceiling and drip water that lands nowhere else.

Bring a spare shulker: the reason most trips end early is a full inventory of moss, and you cannot craft a single one of the thirteen at home. Big Dripleaf Stem is on that list as well.

Moss Block and Moss Carpet cover the floor, Cave Vines hang from the ceiling with berries lighting the vines from inside, and Big Dripleaf and Small Dripleaf stand where the water pools. A moss carpet under a dripleaf is the whole biome in two blocks.

Rooted Dirt with Hanging Roots under it, an Azalea over it, Cave Vines down the wall and a Spore Blossom on the ceiling: that is the whole cave in one photograph.

Moss Block

Moss Carpet

Glow Berries

Cave Vines

Dripleaf

Azalea

Spore Blossom

Rooted Dirt

Hanging Roots

Everything here grew rather than got built. No build belongs to lush caves, so the reward for breaking into one is the cave vegetation itself: moss over the floor, cave vines hanging with glow berries, dripleaf over the clay pools and azalea trees marking the roof from above.

Because the biome is already underground, everything the world digs runs straight into it. Mineshaft tunnels break through the moss walls, dungeon rooms sit against them, and a stronghold can share the same stretch of stone. A lush cave with a mineshaft cutting through it is the cheapest lighting job you will ever do. Scenery no surface biome can match is what exploring rewards, rather than buildings, and the dungeons and mineshafts that break in, an occasional stronghold with them, were generated with no regard for boundaries. Loot, if there is any, comes out of those. Generation dug them, tied to nothing, and it ignores where a biome starts. Such a break is as good a way in as any, and the moss still grows right up to it.

Eight passes belong to this biome alone, more than any other cave in the game. Cave vines get 188 tries per chunk, classic vines 256, ceiling vegetation 125, floor vegetation another 125, clay 62 and spore blossoms 25. A rooted azalea tree comes once or twice per chunk, and clay gets an extra ore pass at 46 tries. Forty seven passes in total.

Tropical fish are allowed to spawn at any height in the lush caves, and this is the only biome in the world where that rule applies. Everywhere else they need to be near the surface.

That is why an axolotl in a cave pool has something to hunt, and the biome is on the stronghold list even though it sits underground.

The lush caves build nothing of their own. Everything you find down here arrived through the same door as anywhere else: a mineshaft cutting through, a stronghold landing on top of it, or a trial chamber in the -40 to -20 band.

That is why the moss and the azalea feel undisturbed: nothing on that list belongs to the biome itself.