Generating Patches in World Generation

When you want to generate a patch of blocks in Minecraft Bedrock, you have two primary methods depending on what the patch represents. The first and most common method for surface decoration is chaining a `minecraft:scatter_feature` to a `minecraft:single_block_feature` (or `minecraft:weighted_random_feature`). In this setup, the feature rule picks a chunk and a general center point for the patch, the scatter feature runs a loop to pick multiple random coordinates around that center, and the single block feature attempts to place your plant or block at each chosen coordinate.

The second method uses `minecraft:vegetation_patch_feature`. This feature type is built for biome-style terrain splotches, like the moss patches in Lush Caves or mud pools in Mangrove Swamps. Rather than just placing blocks on top of existing dirt, a vegetation patch actually replaces a disk of the ground itself with a new substrate block and optionally triggers a secondary feature (like tall grass or custom flora) to grow directly on top of the newly placed ground.

To build a standard flower or pumpkin patch, you need three separate JSON files in your Behavior Pack: a feature rule, a scatter feature, and a single block feature. The feature rule (`BP/feature_rules/`) acts as the entry point, deciding which biomes the patch spawns in and finding the initial heightmap coordinate. Instead of scattering individual flowers across the entire chunk from the feature rule, you only run the feature rule once or twice per chunk to establish the patch's center.

The `minecraft:scatter_feature` is what actually creates the clustered shape. By using a `gaussian` (bell-curve) distribution for the X and Z coordinates within the scatter feature, most of your blocks will bunch up near the center point, with fewer blocks spawning toward the outer edges. For each scattered coordinate, you use the `query.heightmap` Molang expression on the Y axis so every individual flower snaps cleanly to the terrain surface rather than floating in the air or burying itself into a hillside.

{
  "format_version": "1.13.0",
  "minecraft:scatter_feature": {
    "description": {
      "identifier": "wiki:custom_flower_patch_scatter"
    },
    "places_feature": "wiki:custom_flower_single_block",
    "iterations": 32,
    "x": {
      "distribution": "gaussian",
      "extent": [ -6, 6 ]
    },
    "z": {
      "distribution": "gaussian",
      "extent": [ -6, 6 ]
    },
    "y": "query.heightmap(variable.worldx, variable.worldz)"
  }
}

The `places_feature` field in your scatter feature points to the leaf feature that places the actual block. A `minecraft:single_block_feature` is ideal here because it lets you enforce strict survival and attachment rules for each attempt in the scatter loop. Even if the scatter feature runs 32 times, only the attempts that land on valid ground will succeed, which naturally thins out the patch around rocks, water, and trees.

In the single block feature below, `may_replace` ensures the block only spawns in empty air, and `may_attach_to` guarantees it only places on top of grass or dirt. If you want a mixed patch—such as a mix of red poppies, dandelions, and fern—replace the single block feature with a `minecraft:weighted_random_feature` that selects between several different single block features.

{
  "format_version": "1.13.0",
  "minecraft:single_block_feature": {
    "description": {
      "identifier": "wiki:custom_flower_single_block"
    },
    "places_block": "minecraft:red_flower",
    "enforce_survivability_rules": true,
    "enforce_placement_rules": true,
    "may_replace": [
      "minecraft:air"
    ],
    "may_attach_to": {
      "bottom": [
        "minecraft:grass_block",
        "minecraft:dirt"
      ]
    }
  }
}

When your patch needs to alter the ground material itself, reach for `minecraft:vegetation_patch_feature`. This feature scans vertically within a given `vertical_range` to find a surface matching your `replaceable_blocks` list. Once found, it carves out a rough circle based on `horizontal_radius` and fills it down to `depth` with your chosen `ground_block`.

On top of the newly placed substrate, the feature can automatically run another feature for every surface block it creates, controlled by `vegetation_chance`. This makes it effortless to generate things like a corrupted mycelial patch that replaces grass with mycelium and immediately sprouts mushrooms on top, all from a single feature file.

{
  "format_version": "1.16.0",
  "minecraft:vegetation_patch_feature": {
    "description": {
      "identifier": "wiki:mossy_ground_patch_feature"
    },
    "replaceable_blocks": [
      "minecraft:stone",
      "minecraft:dirt",
      "minecraft:grass_block"
    ],
    "ground_block": "minecraft:moss_block",
    "vegetation_feature": "wiki:custom_flower_single_block",
    "surface": "floor",
    "depth": {
      "range_min": 1,
      "range_max": 2
    },
    "vertical_range": 5,
    "vegetation_chance": 0.25,
    "horizontal_radius": {
      "range_min": 3,
      "range_max": 6
    },
    "extra_edge_column_chance": 0.3
  }
}

Neither a scatter feature nor a vegetation patch feature will appear in the world until it is called by a feature rule in `BP/feature_rules/`. For surface patches, set the `placement_pass` to `surface_pass` or `vegetal_decoration_pass`. Using `surface_pass` is generally best for `minecraft:vegetation_patch_feature` so the ground swaps out before vanilla trees and flowers try to generate on top of it.

In the feature rule's `distribution` object, keep `iterations` to `1` and control the rarity of the entire patch using `scatter_chance`. If you put a high iteration count in the feature rule AND a high iteration count in your scatter feature, you will multiply the placements and coat the entire chunk in blocks instead of getting distinct, isolated patches.

{
  "format_version": "1.13.0",
  "minecraft:feature_rules": {
    "description": {
      "identifier": "wiki:overworld_flower_patch_rule",
      "places_feature": "wiki:custom_flower_patch_scatter"
    },
    "conditions": {
      "placement_pass": "vegetal_decoration_pass",
      "minecraft:biome_filter": [
        {
          "test": "has_biome_tag",
          "operator": "==",
          "value": "plains"
        }
      ]
    },
    "distribution": {
      "iterations": 1,
      "scatter_chance": 10.0,
      "x": {
        "distribution": "uniform",
        "extent": [ 0, 16 ]
      },
      "z": {
        "distribution": "uniform",
        "extent": [ 0, 16 ]
      },
      "y": "query.heightmap(variable.worldx, variable.worldz)"
    }
  }
}

Scatter, single block, and feature rules are stable in format version 1.13.0 and above. `minecraft:vegetation_patch_feature` requires format version 1.16.0 or higher. No experimental toggles are needed for any of these features in current Bedrock releases.

Read out of the game itself, so the ids match the version you are building for.