Food is what makes the empire grow and one of the strategic elements of a planet's economy.
Food is useful for one purpose and one purpose alone: population growth. Increasing a planet's population and then maintaining that level. This also makes it the most important resource in the long term, as a high population impacts every area of an empire's performance: Research, production, and especially income.
Optimizing food production
- For a list of structures that affect the food output of a planet, see Colony structures#Food
- Biomes are an important part of the optimizing process. On lower class planets, you'll have to assign multiple workers to have the same yield as a single one on a higher class planet. Terraforming is a cheap long-term way to improve a planet's food output.
- Colony structures are an obvious way to improve food production. The highest priority improvements are those that reduce the amount of food needed to gain a population point, as they maximize the effect of farming without directing additional manpower that way.