Genetics
From Unofficial Stationeers Wiki
Plants have a set of Genes that modifies its behavior. A plant's genes will be manipulated in a number of ways, both naturally as well as artificially. When a plant produces fruit or seeds it will pass on its genetics with a small random mutation.
On top of random mutations, a plant's condition over its life can also affect its genes - for example if a plant is starved of water, while it may affect the plants growth speed and vield, the offspring will receive genes that make it require less water. In this way vou can manipulate your crop's ideal conditions.
There are a number of tools you will need to manage your crops effectively: Plant Sampler and Plant Genetic Analyzer. These tools allow vou to sample a growing plant and see the state of its genes.
Plant genetics is not an exact science and will require trial and error and repeated attempts before you are able to reach your targets.