Grass enables many plants to grow on it, and covers most of the aboveground landscape. There are six types of grass: Normal, Corrupt, Crimson, Mushroom, Jungle and Hallowed.
Natural grass types
Internal Tile ID: 2
|Green||Dirt||Surface of Forests, Floating Islands||Trees, Mushrooms, wild Grass, Dayblooms, Yellow Marigolds|
Internal Tile ID: 23
|Purple||Dirt||Surface of The Corruption||Corrupt trees, Vile Mushrooms, wild Corrupt grass, Deathweed, Thorny bushes|
Internal Tile ID: 199
|Red||Dirt||Surface of The Crimson||Crimson trees, Vicious Mushrooms, wild Crimson grass, Deathweed, Thorny bushes|
Internal Tile ID: 70
|Blue||Mud||Glowing Mushroom biome||Glowing Mushrooms, Giant Glowing Mushrooms|
Internal Tile ID: 60
|Lime green||Mud||Jungle, Underground Jungle||Jungle trees, wild Jungle grass, Moonglow|
Underground Jungle: Thorny bushes, Jungle Spores, Jungle Roses, Moonglows, Nature's Gifts
Internal Tile ID: 109
|Cyan||Dirt||Surface of The Hallow||Hallowed trees, Mushrooms, wild Hallowed grass, Dayblooms|
Mowed grass types 
Internal Tile ID: 477
|Green||Dirt||Lawn Mower used on grass|
|Mowed Hallowed grass
Internal Tile ID: 492
|Cyan||Dirt||Lawn Mower used on Hallowed grass|
Wild Grasses and Plants
|Grass||May drop Grasshoppers, Worms or their gold variants.|
|Corrupt Grass||Drops nothing. Contributes to Corruption biome tile count.|
|Crimson Grass||Drops nothing. Does not contribute to Crimson biome tile count.|
|Hallowed Grass||Drops nothing. Contributes to Hallowed biome tile count.|
|Jungle Grass||May drop Grubby, Sluggy, Buggy or Jungle Grass Seeds. Contributes to Jungle biome tile count.|
- Normal grass spreads over Dirt Blocks. Above ground grass blocks will grow Mushroom, Daybloom, flowers, and weeds, all of which can be cut with any tool or weapon. If a grass block has room below it, vines will grow downward from it. Grass is necessary in order to plant trees, Pumpkins, and Sunflowers. Grass does not spread below 0 elevation, but can be placed in lower layers block by block using the Staff of Regrowth or Grass Seeds. This grass will not grow flowers and tall grass, and trees planted on it will never mature. Grass occurs naturally above ground, but it may also be planted by using Grass Seeds bought from the Dryad. It can also be mowed with a Lawn Mower.
- Corrupt grass converts normal grass, and spreads over Dirt Blocks in lieu of normal grass. Above ground Corrupt grass can sprout Vile Mushrooms, Deathweed, corrupt flowers, and weeds, all of which can be cut with any tool or weapon. In addition, Corrupt thorns will grow from Corrupted grass in any direction, also spreading Corruption. Vines do not grow from Corrupt grass. Like normal grass, it does not spread below 0 elevation. This type of grass occurs naturally in the Corruption. It can be created with Corrupt Seeds, Clentaminator with Purple Solution, or Unholy Water. A large amount of Corrupt grass ( 300 / 200) will turn the area into a Corruption biome. In Hardmode, any grass growing on dirt can be converted into Corrupt grass if it is within three tiles of a Corrupt block (Corrupt grass, Ebonstone, Purple Ice, Ebonsand, Hardened Ebonsand). Corrupt grass will convert infectable blocks (grass, stone, ice, sand, hardened sand, sandstone) that are up to three tiles away into their Corrupt variants. This can result in grasses below 0 elevation converting into Corrupt grass. Corrupt grass can convert mud into dirt, unless the mud is covered by Mushroom grass; in this manner, it can convert Jungle grass. It also gives off particles.
- Crimson grass converts normal grass, and spreads over Dirt Blocks in lieu of normal grass. Above ground Crimson grass can sprout Vicious Mushrooms, Deathweed, crimson flowers, and weeds, all of which can be cut with any tool or weapon. In addition, Crimson thorns will grow from Crimson grass in any direction, also spreading Crimson. If a Crimson grass block has room below it, Crimson vines will grow downward from it. Like normal grass, it does not spread below 0 elevation. This type of grass occurs naturally in the Crimson. It can be created with Crimson Seeds, Clentaminator with Red Solution, or Blood Water. A large amount of Crimson grass ( 300 / 200) will turn the area into a Crimson biome. In Hardmode, any grass growing on dirt can be converted into Crimson grass if it is within three tiles of a Crimson block (Crimson grass, Crimstone, Red Ice, Crimsand, Hardened Crimsand). Crimson grass will convert infectable blocks (grass, stone, ice, sand, hardened sand, sandstone) that are up to three tiles away into their Crimson variants. This can result in grasses below 0 elevation converting into Crimson grass. Crimson grass can convert mud into dirt, unless the mud is covered by Mushroom grass; in this manner, it can convert Jungle grass. Crimson vines can spread Crimson to any grass below.
- Mushroom grass spreads over Mud Blocks and will grow Glowing Mushrooms and Giant Glowing Mushrooms and can be found underground at a depth of 0 feet or below. Patches of mud seeded with Mushroom grass can be found in some caverns underground, generally with several tall Giant Glowing Mushrooms. Mushroom Grass Seeds are an uncommon drop from Glowing Mushrooms and Giant Glowing Mushrooms. Mushroom grass glows faintly and can be used as a natural light source. Mushroom grass is unaffected by Corruption or Crimson, but the uncovered mud is. When above ground, Mushroom grass and the Mushrooms on it actually grow faster.
- Jungle grass spreads over Mud Blocks at any depth, and will grow Jungle vines, Jungle thorns, Moonglow, Jungle Spores, Jungle Roses, and Nature's Gift. Jungle grass occurs naturally in the Jungle and Underground Jungle area but can also be planted from Jungle Grass Seeds which are a rare drop from Jungle grass weeds and glowing flowers. Jungle plants grow underwater in contrast to other plants. Similar to Mushroom grass, Jungle grass spreads faster above surface level.
- Hallowed grass converts normal grass, and spreads over Dirt Blocks in lieu of normal grass. Above ground Hallowed grass will grow Mushroom, Daybloom, and flowers, similar to normal grass. Like regular grass, Hallowed grass does not spread below 0 feet elevation. Hallowed grass does not occur naturally until a world enters Hardmode, and may be created with Hallowed Seeds sold by the Dryad in Hardmode or with Holy Water. A large enough amount of Hallowed grass will turn the area into a Hallow biome. In Hardmode, Hallowed grass will convert blocks that are up to three squares away into their Hallowed variants, although it does not turn Jungle grass into Hallowed grass. It gives off a sparkle particle effect. It can also be mowed with a Lawn Mower.
- Mowed grass is made by mowing Normal and Hallowed grass with a Lawn Mower sold by the Golfer. Mowed grass has a different texture, reduces enemy spawn chance, prevents tall grass from growing, and changes how Golf Balls move in golfing.
Grass of any type spreads from existing blocks to other blocks of the correct soil type. Corrupt, Crimson, and Hallowed grass can even – with certain restrictions – spread to and convert each other.
If painted grass spreads to adjacent Dirt/Mud Blocks, it will spread the paint too. Furthermore, tall grass, flowers, or Glowing Mushrooms growing on the colored grass will take on the same color. This does not always extend to trees, Giant Glowing Mushrooms, or dye plants.
- Note that when mining blocks with grass, the grass will absorb the first hit from the pickaxe. So unlike mining most blocks, a tool with high mining speed will actually always outperform a slower tool, even if the slower one has higher pickaxe power. This means that the best pre-Hardmode item for digging grass would be the Bone Pickaxe. In theory, the Shroomite Digging Claw has the best speed out of hardmode tools.
- This becomes particularly important in the Jungle biome, due to the prevalence of jungle grass.
- Abigail's Flower can only be grown on normal grass.
- Crimson grass appears to be "Weaker" than Corrupt grass since the Hallow can spread on Crimson grass but not on Corrupt grass.
- There are unused graphics for two other grass types in the game's files. One is a yellow-green grass akin to Jungle Grass, although it is tiled on dirt. Its internal name "
Tiles_2_Beach.png" implies that it was originally intended for the Ocean. The second is a variation of Flesh Blocks, tiled to work as a grass.
- Crimson grass is referred to as "
FleshGrass" internally, so the second grass variation may have been an early crimson grass sprite.
- Crimson grass is referred to as "
- Desktop 220.127.116.11:
- Artificial Jungle biomes now require 140 Jungle grass blocks instead of 100.
- Added mowed grass.
- Desktop 1.2.4:
- Replaced grass graphics for when they are surrounded.
- Grass is now removed when a player covers it in solid tiles.
- Desktop 1.2.3:
- Desktop 1.2: Crimson grass variant introduced.
- Desktop 1.1: Hallowed grass variant introduced.
- Desktop-Release: Introduced.