Dirt

Dirt is a common solid resource used throughout the early and mid game as a construction material, fertilizer, and ingredient in several production buildings. It naturally occurs in the Temperate Biome and Forest Biome, making it one of the first renewable-ish materials a colony can gather in large amounts before more advanced resource loops are established.

Dirt is consumed by several basic buildings and production chains. It is used to build Planter Boxes, Farm Tiles, and Algae Terrariums, and it is also required by Research Stations for basic research. Microbe Mushers use Dirt together with Water to make Mush Bars, while Outhouses consume Dirt and output Polluted Dirt. In medicine, the Apothecary can combine Blossom Seed and Dirt to produce Allergy Medication.

Several domesticated plants require Dirt as fertilizer. The documented rates are:

• Mealwood: 10 kg/cycle
• Sleet Wheat: 5 kg/cycle
• Nosh Sprout: 5 kg/cycle
• Oxyfern: 4 kg/cycle
• Arbor Tree: 10 kg/cycle
• Gas Grass: 25 kg/cycle

Dirt also serves as an input for Fertilizer Synthesizers, which can convert Polluted Water, Dirt, and Phosphorite into Fertilizer while producing Natural Gas as a byproduct. This makes Dirt an important part of large-scale farming setups, especially when a colony is trying to sustain multiple domestic crops or fertilizer production.

Dirt can be obtained from a number of sources and processing chains:

• Compost converts Polluted Dirt into Dirt at 100% efficiency, at the cost of duplicant labor and waste heat.
• Boiling Polluted Water into Steam leaves a small amount of Dirt behind.
• Filtering Polluted Water with a Water Sieve produces Polluted Dirt as a byproduct, which can then be composted.
• Heating some organic materials such as Slime, Algae, and Fertilizer above 125°C converts them into Dirt.
• Ethanol Distillers generate Polluted Dirt from Lumber, which can then be composted into Dirt.
• Pips can harvest dirt from Arbor Trees and Thimble Reeds indirectly through plant growth interactions.
• Mud can be converted into Dirt and Water with a Sludge Press, or heated into Dirt and Steam.
• Dirt can also be gathered from certain space missions in Organic Mass Fields.

Dirt is not especially valuable as a late-game raw material, but it remains relevant for a long time because of how many early systems rely on it. Its main strategic value lies in supporting farming, feeding research, and acting as a sink or intermediate product in compost-based resource loops. Hatches and Sage Hatches can eat Dirt and convert it into Coal, and Shove Voles can also consume Dirt, though that is usually inefficient.

Because Dirt is used in so many places, colonies that rely heavily on domesticated farming or basic research often need to keep a steady supply on hand. Once a stable source is established, it becomes one of the most flexible and easy-to-route resources in the colony.