|This article is suggested to be rewritten. Reason: Cleanup and clarity. You can help RimWorld Wiki by improving it.|
Plants are passive, flammable objects available in numerous species of different appearance, growth rate, lifespan, fertility requirements, and biome. Plants are generally passable, minifiable, provide no cover, and are not susceptible to Sharp or Blunt damage (except trees, cacti, and bushes.) All plants can be destroyed by Fire, cutting, a Defoliator ship, or being consumed by an animal. Plants may spontaneously grow in available tiles or can be cultivated by colonists in growing zones or hydroponics basins. With adequate time and environmental conditions, plants will age into a mature lifestage when they can be harvested by colonists assigned to Grow work.
Growth rate factors
Fertility is a measure of a location's efficacy for growing plants. Most plants have a Fertility requirement of at least 50% (except trees at a measly 30% Fertility). Plant growth speed is also positively correlated to soil Fertility. However, fertility does not affect the harvested yield from a plant, just the time to mature to that yield. Different terrains or growing apparatuses have different fertilities.
Most plants have a <fertilityFactorGrowthRate>, which is used to determine how "picky" a plant is about terrain fertility. Ingame, this is also denoted as "Fertility sensitivity". A plant with a <fertilityFactorGrowthRate> of 0 will not care if it is planted on fertile soil or sand; it will grow at the same rate on any possible terrain tile. In contrast, a plant with a <fertilityFactorGrowthRate> of 1 will not grow so well if it is planted on anything less fertile than standard soil.
Note: Beyond 100% Fertility, high Fertility Sensitivity becomes a bonus rather than a penalty. For such cases highly sensitive plants are preferable.
(GRF(F)) Growth Rate Factor(Fertility) = (Fertility ÷ 100% − 1) × fertilityFactorGrowthRate + 1
The table below lists the fertility of different terrains and other valid places to grow crops. Note that not all of the below support all plants - for example, trees cannot be grown in hydroponics basins, even though the basin's fertility is above their fertility requirement.
For normal growth rate, plants require temperature between 10 °C (50 °F) and 42 °C (107.6 °F). Plant growth rate drops by 10.0% for each degree Celsius below 10 °C (50 °F), and by 6.25% for each degree above 42 °C (107.6 °F). The plant's info window will show 'Non-ideal temperature. Temperature growth multiplier: #%'. Plants will not grow when the temperature falls below 0 °C (32 °F) or rises above 58 °C (136.4 °F). The plant's info window will show 'Non-ideal temperature. Not growing.' If the temperature drops below -10 °C (14 °F), the plant will either die or lose its leaves, depending on its type. This is obvious on trees, because it shows a new graphic with no leaves on it, but it actually applies to all wild(?) plants, including grasses. Leafless plants are inedible by animals. This may cause problems to inexperienced players, as it's unrealistic and the game doesn't give a hint on why colony's animals stop grazing and starve, the plants seem perfectly normal upon close examination. It takes 24 hours to regrow leaves after the temperature rises back above -2 °C (28.4 °F), the plants cannot grow before then, despite possibly high enough temperature.
The actual values of temperature and temperature growth multiplier are unseen real numbers, the game only shows rounded values. Thus, it is possible, for example, to see a 3% multiplier at 58°C (the actual temperature may be 57.52°C).
(GRF(T)) Growth Rate Factor(Temperature) = Temperature ÷ 10°C ; Temperature < 10°C
(GRF(T)) Growth Rate Factor(Temperature) = 1 ; 10°C ≤ Temperature ≤ 42°C
(GRF(T)) Growth Rate Factor(Temperature) = (58°C − Temperature) ÷ 16°C ; Temperature > 42°C
Most plants typically require at least 51% light to grow.
Decorative Plants typically require at least 30% light to grow.
When a plant lacks adequate light its info window indicates this with the text 'Needs light level: ##%'. Over that minimum a plant's growth rate will increase until it reaches its optimal light level (100% standard).
- Example: Rose (Needs light level: 30% Optimal light 100%). In soil or Plant pot (Fertility 100%) under Standing lamp Light (50%) growing Speed 29%)
Most artificial light sources only provide 50% light. Only decorative plants, tinctoria, and fibercorn can grow under such poor light conditions. The sun lamp provides 100% light in its radius, and is thus usually required for any indoor growing.
- (GRF(L)) Growth Rate Factor(Light) =
(Light − growMinGlow) ÷ (growOptimalGlow − growMinGlow)
In mods, this minimum light value can be modified by changing a plant's <growMinGlow> value. A plant's optimal light level can be modified by changing its <growOptimalGlow> value.
All plants rest from hour 19 through hour 5. More accurately, plants rest for 11h of the day, leaving 13h of the day for growing.
During the plant resting time period, plants will not grow no matter the light level.
A new constant, Growing Ticks/Day, can be found by multiplying Ticks/Day by 13/24 (approx. 54.167%) :
Growing Ticks/Day = (60,000 Ticks/Day × 13/24) = 32,500 Ticks
All plants receive an instantaneous growth of 5% when sown (planted).
This is relevant because it means that all plants only need to grow 95% from the moment they are sown to become fully grown (100%).
You'll see this show up in a later equation as a new value: Growth Remaining
You can use this value to help determine how long a plant has left before it is fully grown.
Growth Remaining = 1 − 0.05 = 0.95
- Plant was just sown
Growth Remaining = 1 − Current Growth < 0.95
- Plant was sown some time ago
Actual growth time
The Growth Time displayed in-game can tend to confuse a player into thinking a plant will be fully grown in X number of days.
Due to the various Growth Rate Factors (Fertility, Temperature, Light) and every plant's need to rest, the growDays or "Growth Time" listed in-game is not an accurate/intuitive representation of how long a plant actually takes to grow.
For example: A Raspberry Bush (3:growDays), on Soil (1:Fert), experiencing optimal temperature and light 100% of the time (1:Temp, 1:Light), will take approximately 5.18 actual in-game days to grow.
It is important to remember this when setting up your growing zones.
Actual Growth Time = (Growth Remaining × 60,000 Ticks/Day × growDays) ÷ (Growing Ticks/Day × GRF(F) × GRF(T) × GRF(L))
If they are not harvested or eaten, plants will eventually die. The message will be named <plant> died from rotting. The counting of their lifetime starts when the plant is sown/spawned. Since plants only grow during certain hours, and growth rate varies greatly under different circumstances, it is possible for a plant to die before it reaches full maturity or even while still on the initial progress. A plant will also die from rotting if it is completely deprived of light - for example, if a roof is built over it.
The lifespan of a plant is calculated by multiplying the plant's growDays by its lifespanFraction.
Most vanilla plants have a default lifespanFraction of 5, but some go as high as 8. Trees have this property as well, but due to their long growth time (growDays), their lifespan is longer than is generally relevant.
Types of plants
There are no clear categories of plants provided by the game. For the purpose of easier comparison, plants can be split in the following categories. Note that many plants fall in more than one category.
- Wild plants are plants that can't be planted by the player.
- Decorative plants are plants that can be planted by the player and which main purpose is to add Beauty to a room or area.
- Trees are plants that yield wood or have "tree" in their name.
- Domesticated plants are plants that can be planted by the player and yield something else than wood.
- Food plants are plants that yield food.
- Resource plants are plants that yield something else than food and wood.
|Grow Days||Real Grow Days||Harvest Yield||Yield Per Day (Gravel)||Yield Per Day (Normal)||Yield Per Day (Fertile)||Yield Per Day (Hydroponic)||Fertility Sensitivity|
Real Grow Days = Grow Days ÷ 0.5417
Nutrition per Day = Harvest Yield × Nutrition (0.05) ÷ Real Grow Days
|Beauty Base||Grow Days||Real Grow Days||Lifespan||Fertility Sensitivity||Sow Work|
|Grow Days||Real Grow Days||Beauty Base||Harvest Yield||Harvest Product||Fertility Sensitivity|
|Wild healroot||10||18.46||1||Herbal medicine||1|
|Beauty Base||Grow Days||Real Grow Days||Harvest Yield||Yield Per Day (Gravel)||Yield Per Day (Normal)||Yield Per Day (Fertile)||Fertility Sensitivity|
|Chopped stump (Polluted)|
|Gray pine tree||-5||28||51.69||8||0.15||0.15||0.15||0|
|Rat palm tree||-5||28||51.69||8||0.15||0.15||0.15||0|
|Smashed stump (Polluted)|
- This is the fraction of the day were plants don't grow, 0.45 is used in above calculation. Actual growth time for more information
- Normal soil (1.00) is used in above equation.
|This section is a stub. You can help RimWorld Wiki by expanding it. Reason: Please add a reason.|
The yield of plants with products depends on four factors:
- The base yield of the plant
- The maturity of the plant. Plants that are harvested at the first possible moment (at growth 65%) will only grant half of the total normal yield; this scales linearly towards full harvest as the growth percentage increases. This gives a slight penalty to early harvests.
- The health of the plant. Damaged plants will lose up to half of their yield. A plant at 50% health will lose 25% of the yield.
- The Plant Harvest Yield of the harvesting pawn which acts as a scalar on the resulting number.
- The Harvest Yield storyteller variable - note that Difficulty settings change variable even if a custom difficulty is not selected.
As plant harvest yield increases with Plants skill, pawns with the highest skills should ideally be used to harvest plants, while any pawn can be used to sow them.
Plants per pawn
|This section is a stub. You can help RimWorld Wiki by expanding it. Reason: Needs table with list of plants showing plants/human.|
The number of food-bearing plants required per pawn depends on a number of factors, including:
- Hunger rate of the pawn
- Soil type, including the use of hydroponics
- Meal type's nutrient efficiency
- Whether meat is available
- Light times including the effect of latitude, sun lamps, and sun blocking events and condition causers such as Eclipses
- Plant Harvest Yield of the harvesting pawn
- Whether pawns are allowed to eat before they are hungry enough to reap the full benefit from the nutrition offered by the meal.
- Whether the pawn has a large enough Saturation bar to reap the full benefit from the nutrition offered by the meal.
|Plants per Pawn = Hunger rate ÷ (Yield per Day × Nutrition of each harvested item × Nutrient efficiency of the meal × Plant Harvest Yield)|
Plant growth approaches
The player has a number of options to get plants grown for food and raw material. Each of them has their up- and downsides and a proper mix of them is necessary to be resistant to disruptions, including seasons.
You just define a growing zone, select the crop and let nature and your pawns set to growing do the rest.
- No cost, excluding the work time to clear trees, sow crops, and harvesting.
- Available at the start, regardless of technology level
- Outdoor growing is dependent on the local seasonal weather and even impossible in the coldest biomes
- Highly vulnerable to irregular temperature variations such as cold snaps and heat waves that could stop growth or even kill plants
- Outdoor growing is vulnerable to events like toxic fallout and volcanic winter
- Without walls, raiders can easily set your crops ablaze and wild animals can eat your crops. Tamed animals can be excluded via zones however
The Greenhouse is a walled and roofed growing zone, with a sun lamp providing light and heaters or coolers maintaining climate
- Walling off your crops keeps out raiders and wild animals
- Low costs for the walls and sun lamp alone
- Full resistance to temperature variations once heaters or coolers are built
- Slightly increased growth, due to the persistent 100% lighting level from the sun lamp during the day
- Energy shortages will only kill existing plants if the temperature gets too extreme
- Immune to events like toxic fallout and volcanic winter
- Trees cannot be planted in greenhouses
- Needs tiles that can support building walls to support the roof, which is difficult in swamp biomes
- Sun lamps require incredible amounts of power during the day: 1-2 solar generators worth of production for the entirety of the plant's non-rest cycle
- High energy costs for maintaining sun lamps
- Requires electricity research to unlock
Open roof greenhouses
Only indoor rooms can control temperature, however any room is considered indoors so long as less than 1/4 of the tiles are unroofed, up to a limit of 300 unroofed tiles. Though unroofed sections increase the rate of temperature equalization significantly, this allows the creation of greenhouses that can be used to grow trees, which cannot usually be grown under roofs, or even without sun lamps.
These are constructed like most greenhouses, but with the remove roof area order used to remove 1 tile fewer than 1/4 of the roof. If for growing trees, these removed areas should be spaced 1 tile away from each other gap both horizontally and vertically, as trees cannot be sown next to each other. For growing traditional crops without a sun lamp, this should all be concentrated in one area to limit time spent traveling from place to place while sowing and harvesting.
Due to the costs of controlling the temperature, using this strategy to avoid the cost of sun lamps may or may not break even depending on the biome and the heating or cooling required. In cold biomes, combination with a steam geyser can significantly reduce heating costs, making this strategy much more viable regardless of the intent. If using campfires to heat the greenhouse, they should be placed in the roofed areas to prevent additional fuel usage during inclement weather.
- Does not require sun lamps or even electricity
- Can support trees, including cocoa trees.
- When used for trees, no larger than is necessary as trees can't be planted adjacent to each other anyway.
- Forces trees to be sown perfectly spaced without having to micromanage it, improving yields/area
- Easy to convert to and from more traditional greenhouses
- Needs significantly more heating/cooling
- 4x larger for the same volume of non-tree greenhouse space
- Slow and/or difficult to adapt to changing weather conditions.
- Net wood-negative when using campfires to grow trees.
Hydroponics allows plants to grow without soil by using nutrients dissolved in a water bath. In-game, it requires research to unlock and the construction of one or more Hydroponics basins. These basins will override any growing zone they are placed on top of.
- Basins provide fertility of 280%, the highest rating in the game
- Plants with high fertility sensitivity grow especially well
- Can be combined with greenhouses for growing in environments too cold or hot for outdoor plant growth, including mountains
- Building a sun lamp and 24 basins (the maximum amount of basins that can fit within a sun lamp's radius of light) requires a huge resource and power commitment, requiring 4580 watts, 1720 steel, and 24 components.
- If the basin loses power, the plants will die within an in-game hour, unless it can be repaired immediately. If not, manually harvest as soon as possible.
- A power outage including solar flares will wipe out the entire plant stock in all basins, requiring extensive replanting and usually disrupting food production.
- There are fewer options for growing crops within hydroponics basins.
- 0.10.785 - Rebalanced and reformatted plant ecology tunings to lengthen crop cycles and slow wild plant spread. Reworked plant growth in relation to light levels so plants can still grow slowly in dim light (e.g. tundra summers).
- Beta 19/1.0 - All non-tree sowable crops yield 20% less when harvested and take 10% longer to sow.