Rust Genetics Calculator

The rule

A plant crossbreeds once, on entering its crossbreed stage. For each of the six slots, every other plant of the same crop in the same planter within 1.5 m contributes the weight of whatever gene it holds in that slot. Those weights are added up per gene. The heaviest gene replaces yours only when its total is strictly greater than the weight of the gene you already have.

There is no random roll in the gene calculation. Tied totals can depend on the order the game reads the donors. By default, the planner avoids these ties. Only the centre reaches its crossbreed stage, so donors do not change first.

The weights, and why they matter

X and W weigh 1. G, Y and H weigh 0.6. Two consequences follow, and between them they explain almost every breeding frustration.

• One neighbour can never overwrite an X or a W, because 0.6 does not beat 1. You need two carrying the same gene, for 1.2.
• A single X or W will overwrite a G, a Y or an H, because 1 does beat 0.6. One bad plant in the planter drags your good ones backwards. That is why breeders pull the empties out rather than leaving them in to fill space.

Every crop reaches its crossbreed stage 21 minutes after planting, at the end of its third stage. That stage lasts one minute for most crops and five for every berry, so berries reach the Mature stage four minutes later than the rest.

You cannot clone a plant during its crossbreed stage: that stage carries no resources, so the game refuses. The sapling stage before it does, which is where you take clones of a plant you want to keep exactly as it is. Taking clones removes the source plant. Replant the clones to grow them. Clones inherit genes precisely; seeds from a harvest roll fresh.

Only plants in the same planter can breed with each other, and only within 1.5 m, so in a large planter opposite corners never interact. How much water the soil holds differs.

Two of these are honest limits rather than missing homework: one is genuinely random in the game, and no tool can remove it.

• lifeLength

  Exactly how many minutes a plant takes to reach the crossbreed. The stage lengths are exact, but the game advances them on a 60 second tick, so the true figure sits a tick or two above the sum rather than on it.

  To settle it: Time one plant on a server with default planttick and compare against the stage sum.

• InvokeRandomized

  Which plant in a planter crossbreeds first. Each plant's tick carries a small random offset and every crossbreed rewrites its own genes immediately, so plants that reach the stage together resolve in an order the game picks.

  To settle it: Nothing to resolve. It is genuinely non deterministic, which is why every plan here plants the centre first, so only one plant is at the crossbreed stage at a time.

• none

  How many seeds a harvest returns. The dispenser tables are not in the bundles this reads.

  To settle it: Locate the growable dispenser tables and extract their yields.