There are 4 components that impact your city growth in Civ 6 Gathering Storm.
First, focus on food to grow your population, because city yields increase as population grows. Each citizen consumes 2 units of food. To increase food production early, improve tiles and build a granary or a harbor with a lighthouse, harvest resources such as bananas and remove features like rainforests.
Sources of food:
- Tiles with food related improvements
- Farms (adjacent farms triangle shape) with Feudalism +1 food; Replaceable Parts +1 food
- Plantation with Feudalism +1 food; Scientific Theory +1 food
- Pasture with Stirrups +1 food
- Fishing Boats +1food with Plastics
- Trade routes, pantheons, gov policies, gov promotions, wonders, natural wonders, buildings and districts
Second, Amenities have either a positive or negative impact on all yields produced by the city including food and therefore population growth. Each citizen requires 2 amenities to stay content.
Amenities are responsible for keeping your population loyal and productive. Each city requires half the number of its population for amenities to be content. So a city of pop 10 will require 5 amenities. Lack of amenities will impact city growth and production.
However, earning extra amenities will allow your empire to become a superpower.
When a city earns 5 or more extra amenities, it reaches Ecstatic level of happiness that grants a 20% bonus to all yields earned by the city – food, production, science, culture and faith! (+3 amenities +10%)
The most common source of amenities are luxury resources which are scattered around the map. You would need to settle a new continent to obtain a new type of luxury resource, or trade with other civs or become a suzerain of a city-state that owns it. The suzerainty of Buenos Aires city-state will convert each bonus resource into a luxury resource and Zanzibar will provide unique luxury resources.
One of the largest sources of amenities is a National Park. Each city that owns a National Park receives +2 amenities and the closest four cities get +1. The bonus effect compounds from multiple parks, so a city that owns a park and is close to the other five parks will receive +7 amenities.
Another source of amenities are Great People provide unique luxury resources or amenities to the cities where they are activated.
Wonders like The Colosseum and Estadio do Maracana are powerful amenity generators. The Colosseum provides +3 Amenities which are extended to each city center within 6 tiles. Estádio do Maracanã adds +2 Amenities to each city in your civilization.
You can earn more amenities from Waterpark and Entertainment Complex districts, as well as the Shopping Mall building from the Neighborhood.
Other sources of amenities include improvements like Ski Resorts and religious beliefs like Zen Meditation.
Some civilizations have amenities bonuses baked into their traits.
Mayan cities gain +1 Amenities for every luxury resource next to the City Center.
Luxury resources improved by Montezuma provide Amenities to 2 extra cities.
Indian cities gain 1 Amenities for each religion with 1 follower in them.
Kupe grants the Palace +1 Amenities
Indonesian Entertainment Complexes built next to a Coast or Lake tile gain +1 Amenities
Khmer Aqueducts provide +3 Faith Faith and +1 Amenities
Cities conquered by the Ottomans gain +1 Amenities
Alexander’s Macedon does not lose Amenities for war weariness.
Lastly, there are various government policies you can implement to raise the happiness of your cities that can propel your civilization to ANY type of victory.
Third, Housing has to be kept at 2 units above the population level for the city to grow at the normal rate. Avoid working excess food yields if there isn’t enough housing, because that food would be wasted. Settle cities on freshwater tiles that provide +3 housing immediately. Other sources of housing are similar to food
Improve tiles, farms, plantations and fishing boats provide 0.5 housing
Buildings (granary, sewer, seaport), pantheons, districts (aqueduct, neighborhood, dam, preserve), gov policies, gov promotions, wonders, natural wonders, great people
The Fourth component is Loyalty that has only negative impact when it falls below the level of 75. Grow your population and keep amenities high to avoid a revolution.