Coarse Dirt

"Dirt has a ruder, less friendly cousin called "coarse dirt" that won't grow grass under any circumstances. You can make it by combining dirt with gravel in a 2x2 crafting grid, or hunt some down in the Mega Taiga, Mesa Plateau or Savanna Plateau biomes."

- Duncan Geere

Coarse dirt is a variation of dirt that grass blocks won’t spread on.

Obtaining
Coarse dirt will drop as an item when mined with anything, but using a shovel is quickest.

Natural generation
Coarse dirt can be found in all Giant Taiga variants, Modified Wooded Badlands Plateau, and Shattered Savanna Plateau biomes.

Usage
Coarse dirt has the ability to grow saplings, sugar canes, and mushrooms, which can be planted directly under appropriate conditions.

Neither mycelium nor grass will spread onto coarse dirt.

Coarse dirt can be tilled to become dirt. This can be useful in multiplying dirt, assuming you have a steady source of gravel.

Grassless dirt
In Bedrock Edition, the corresponding block, known as "grassless dirt", is simply dirt with a data value of 1. It has most of the same properties as coarse dirt, except that it has the texture of regular dirt, it drops a regular dirt block when broken even with Silk Touch, it cannot be crafted, and when tilled it turns to farmland rather than regular dirt.