- 1 Typical colonization method
- 2 Colonization through diversity
- 3 Choosing worlds to colonize
- 4 Colony ship
- 5 Colony development
- 6 References
Typical colonization method
Each species begins with a partially-developed Homeworld. This world is always of the type chosen during Empire creation, and always has 16 or more surface tiles and a hardcoded habitability of 100% for that species. Some of the tiles are blocked by Sprawling Slums and Industrial Wastelands, special Tileblockers that need less resources and no technology to remove. In order to expand, the species can build colony ships to send to other habitable worlds.
Through the entire game only planets with at least 40% habitability can be colonised (for certain types of world, a particular technology is also required). The primary source of habitability is from the species Habitability trait: Planets of the same type have 80% Habitability, planets within the same Hydrosphere group have 60%, and planets belonging to other groups have 20%. Gaia Worlds and space habitats always have 100% habitability for any species.
Typically, in order to colonize other planet types you must do one of these things:
- Terraform the planet to a more habitable type.
- Increase the diversity in your empire to include a species than can colonize other planet types. If you conquered primitives you need to wait for culture shock to wear off.
- Complete the research items that increase the species' habitability empire-wide.
- Use Droid or Synthethic pops as initial colonists.
Colonization through diversity
It is possible to colonize planets of radically different environments without terraforming or genetic engineering. Stellaris provides several methods by which you can mold a species to better fit its environment, rather than molding the environment to fit the species. You should be aware that these methods are typically disliked by most imperial species. The methods are:
Using other species of an empire
This approach may work if you have few different organic species in your empire and they have different planetary preferences. If your main species hates deserts, but you have some citizens of a desert loving species, you can send them to colonize a desert planet. Of course, you will need to be careful with this process, as they may have very different ethos from the imperial one, or they may come to generally dislike you. You don't want them to turn into separatists as soon as they claim the new faraway planet. The best way to do this, is using Uplifted pre-sentient species. They are usually loyal to the empire that brought them to the sentience and may have unique genetic traits making them capable of inhabiting extreme environments. Some of them even have traits enabling them to easily inhabit irradiated Tomb Worlds.
Using Droids or Synthetics
You can put a Droid or Synthetic pop on a colony ship and send it to colonize any planet, even with 0% habitability, because robotic citizens always have 100% habitability on all planets. However, robots don't reproduce. This means that unless you actively manage the colonization, once the colony appears on the planetary surface the planet will never have more than the one initial pop. You can avoid this building more robotic pops to be built, or resettling or migrating organic pops. Some drawbacks to this approach are that Droids get a big penalty to Research tile yields (and smaller for Energy), though Synthetics are free of such limitations. Colonizing with droids or synthetics is a good way to gain control of planets with pre-sentient species for uplifting, if your own species does not have the ability to colonize those planets.
Genetically re-engineering your main species
This is possible once you have researched Social Technology of Gene Tailoring. Both deliberately and via the Environmental Adaptation event. See Genetic engineering for details.
Choosing worlds to colonize
Planets differ mainly by habitability and size and which of those two should be your primary focus depends on the Empire you are planing on playing. Habitability is important if you are going for a high happiness build (as habitability caps happiness) or if you want rapid population growth (to increase borders and work a lot of tile quickly). Size in turn is very important for Research, as there is a penalty to research cost based on number of planets and pops. As such 2 size 12 planets are significantly worse than 1 size 24. Having a large number of planets (regardless of habitability and sizes) is only useful to build additional ports for Naval Capacity purposes.
Other things worth considering:
- Tile resources - planets have base resources randomly distributed across their tiles. Each tile may contain 0-3 units of one of following yields: food, energy, minerals, one of three types of research, or mix of minerals/food or minerals/energy. You should focus on colonizing planets with yields most needed by your empire in the short term... or long term.
- Planetary modifiers - there are over 20 planetary modifiers for some planets, visible as big circles on top of planetary surface screen. They impact yields (for example "Mineral rich" increases extracted mineral yields by 25%) or population in positive or negative way. Some of them are fairly minor, but others have a huge impact.
- Tile blockers - almost all uninhabited planets have some tile blockers. Tile blockers are "natural obstacles" randomly generated on tiles and preventing them from being colonized, developed and exploited. They vary from toxic swamps to volcanoes, and each tile blocker type has a corresponding technology which can be used to clear it - for a cost in minerals and energy. In the early game, when you have neither proper technology or resources enabling you to remove tile blockers, you should avoid colonizing planets very densely covered in them, as you won't be able to properly develop them for a long time. However, by mid to late game, tile blockers become more and more insignificant obstacles and you shouldn't worry about them.
- Special tiles - some planets have very rare special tiles which may be extremely useful to use - those can be ancient obelisks or abandoned mysterious factories. Your pops can operate them, so planets with them may be worth colonizing. On the other hand, some of them may be dangerous...
- System and neighboring systems of a colonizable planet - when you colonize the planet, it generates borders which slowly increase in radius as the population grows. This means that you can exploit resources of the system it is located in - and, if they are close enough, resources of neighboring systems. Sometimes, it is worth to colonize a 'mediocre' planet just to expand the borders and grab very rich resources of a few systems at once.
- Political location of a planet - On the other hand, you have to be careful - if you colonize systems too close to alien empires, they may be very distressed of you suddenly expanding your imperial borders close to them, and declare you a rival or even declare a war. There is a negative "Border tension" modifier in diplomacy when two empires aggressively expand near each other. You should be very careful about colonizing planets near to the Fallen Empires borders, especially if they are Xenophobic - and keep an eye out for Gaia Worlds marked by the Holy Guardians, as well. That said, sometimes proximity is a benefit rather than a drawback: one can easily "hem in" an empire to cut off their expansion, especially if they rely on Hyperlane travel.
Later in the game, choosing what planet should you colonize isn't that big of a challenge as you will presumably have enough spare resources and technology to cope with any natural obstacles and shortages. However, early game prioritization of good planets is very important. Consider these three potential colony planets:
- A large planet with 3/4 of the surface covered in tile blockers.
- A planet possesses an irradiated modifier which makes pops grow very slowly and unhappily.
- A modestly sized planet that also has decent resources and tiles mostly free from obstacles.
Under these circumstances you should consider colonizing number 3. However, the right choice isn't always that obvious...
To colonize a planet, you need to send a colony ship they can be build at your spaceport from the start of the game.
Colony ships cost 350 minerals and take a year to build. While ordering its construction, you have to choose what pops of a planet constructing it will be colonists. This pop will not be "removed" from the surface of an origin planet. On board of the colony ship you can put pops of your main species of various ethics, other species inhabiting your empire, or advanced robots (precisely, Droids or Synthetics - early Robots cannot colonize planets as they are not sentient at all). Remember: if you colonize the planet with pops of ethics radically different from your "mainstream empire" ethos, or from minority race disliking your empire, there is a risk they may try to declare independence in the future.
Once the Colony Ship is constructed, it costs 8 energy credits to maintain each month - thus you should quickly send it to colonize some planet and not waste your income. However Colony Ships are defenseless and should never be sent into hostile or unsecure territory. Either send them to safe, charted space (you need to survey planet to be able to colonize it anyway) or escort them with your military starships.
When you click on the existing Colony ships, go to the Galaxy View. You may notice colorful globe icons displaying above systems. A green globe means there is a colonizable planet of high habitability in that system, yellow means there is a colonizable planet but it has medium habitability, red means low habitability planets, usually under the Colonization threshold.
To colonize a planet, select the colonization ship, right click on the planet you want to settle, and choose Colonize Planet. You will be prompted to choose where your colony ship will make planetfall.
Unlocking the Trans-Stellar Corporations tradition under Prosperity will allow you to build Private Colony Ships. These cost energy instead of minerals and are also 50% cheaper. If built from the spaceport, there is no direct control which specific pop will be used as colonist - including race or ethos. However, if you use the Expansion Planner to select a planet, you can choose a source planet and a specific species to use- even for private colony ships.
Placing the capital building
When you colonize a planet, you will choose which planet tile will be used as your planetfall location. This will serve as the Planetary Administration for your new colony. Here you need to face your first dilemma. Generally there are two factors you need to consider while placing the initial colony:
- 'Energy - in previous versions, the capital of a planet produced food, but as of 1.5, it produces energy and unity instead. As such, placing the Ship Shelter on a tile with energy is ideal; if this isn't feasible, it's best to place it on a tile with no resources, as opposed to one that produces food, minerals, or research (otherwise, they'll be suppressed).
- Adjacency bonuses - in the future you will be able to upgrade your colony to the Administration Center, which will convey adjacency bonuses (food, energy, or minerals, but not research or unity) to its four neighboring tiles, once developed. So it may be worth to place colony on a tile either not on the 'edge' of a planetary surface (where it has limited number of adjacent tiles) or on a tile which has neighboring tiles rich in these yields. This is a long-term bonus; it will make this planet produce more yields in the future.
When a Colony Ship is instructed to colonize a world, you must select a surface tile as the starting location for your colony. The Colony Ship will land on this tile and convert into a Reassembled Ship Shelter, which acts as the new planet's capital building and can be upgraded as the population grows. When choosing the tile to which you will send your Colony Ship, you should consider the adjacency effect of the capital building. The adjacency effect will increase the food, mineral and energy production of the directly adjacent tiles, if there is a proper production building on said tile. This includes the tiles directly above and below, left and right, but not diagonally.
Therefore, your preference should be to place the capital building next to which naturally produce some Food, Minerals or Energy. The next most preferable tiles are empty tiles, and the least preferable are Research tiles.
Note that you can relocate the Reassembled Ship Shelter for free at any time before upgrading it to a Planetary Administration. This can be useful if the best location is initially blocked by a tile blocker, or if you greedily pick a planetfall tile for its energy yield rather than its adjacency bonuses.
Colonization in progress
After you choose a starting tile for the colony, the Colony Ship will enter orbit around the planet and land on the selected tile. A period of initial development will then occur. This is initially one year, but can be reduced empire-wide by researching the appropriate technologies:
- AI-Controlled Colony Ships.
- Self-Aware Colony Ships.
- Frontier Collectives.
- Frontier Commissars.
While the colony is being established, it is extremely vulnerable: just a few days of orbital bombardment will wipe it out completely.
During this period the new colony does not produce anything, and consumes Energy credits from your empire. Once the colony has been successfully established, a Pop will appear on the capital tile, and a Growing Pop on one other tile. You can then begin to develop the planet by constructing Buildings, clearing Tile blockers, and moving Pops.
Growing the colony
Your new planet will take time to settle. While the colony is establishing itself it will be a steady drain on your economy (-8, the same monthly energy cost as the colony ship). Once the colony is established, this economic anchor will end and the planet will be a part of your core system (unless the colony was founded in a system belonging to a Sector - then it will go under sector's autonomic governance).
Colonized worlds can have a governor assigned to them. Depending on their bonuses, the governor will give different benefits to the planet they have been assigned to manage. Systems containing colonized worlds can also be assigned to Sectors, which will manage most aspects of their development and contribute all generated Research, plus a set percentage of Minerals and Energy Credits generated, back to your empire.
In the beginning, a colony has no spaceport, and only one pop working in one building, the Reassembled Ship Shelter. It is a temporary shelter and you can't build many advanced or regular buildings unless you have a proper Administration building. However Administration requires the planet to have 5 population units.
There are few ways to quickly increase population of a new colony to 5:
- Maintain an empire-wide food surplus
- Build a Frontier Clinic building (+2 society, -5% growth time)
- Encourage voluntary migration with the planetary edict "Land of Opportunity" (+100% migration attraction)
- Force resettlement, if your policies allow
- Build robots - they count towards required 5 population units, and grow independently from organic pops, effectively doubling growth
Once you finally hit 5 population units you may upgrade ship shelter to Administration Center, at that point the planet is finally "civilised". Well, you may also need to remove its tile blockers.