Rust Genetics Guide

How crossbreeding works

A plant crossbreeds once, when it reaches its crossbreed stage (after the sapling stage). It then looks at the other plants of the same crop in the same planter, within 1.5 m. Plants in another planter, other crops and dead plants do not count.

1. Each of the 6 slots is decided on its own.
2. Every neighbour adds its gene in that slot to a score: 0.6 for a good gene, 1 for a bad one. Matching genes add up.
3. The gene with the top score replaces the plant's own gene only if that score is higher than the own gene's value (0.6 for good, 1 for bad). Equal is not enough.
4. If two genes share the top score, the one that got there first wins: the gene whose last donor was planted earlier. It is not random.

So one red neighbour ruins a green slot (1 > 0.6), and it takes two matching green neighbours to fix a red slot (0.6 + 0.6 = 1.2 > 1).

Only the plant that is crossbreeding changes. Its neighbours change later, when they reach their own crossbreed stage.

Where to plant

Large planter slots are 1 m apart, so diagonals count. The middle slot touches all 8 others, which makes it the place for the plant you want to improve.

1. Plant the clone you want to improve in the middle.
2. Plant the donors once it turns into a sapling, in the order the calculator gives. A donor must not reach its own crossbreed stage first, or its genes change before they count.
3. Keep the rest of the planter empty, or grow a different crop there.
4. After the middle plant crossbreeds, take clones from it and plant those.