You can only have one greenhouse per map, been like that since the building was added with Sanctuary DLC.
The Greenhouse is an operations building in Evolution that is unlocked through the Claire's Sanctuary DLC. The Greenhouse is used to grow different types of plants that are then placed in the paleofeeders. There is both a ground and tall version of the paleofeeder. Different herbivores have...
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The Greenhouse is used to grow different types of plants that are then placed in the
paleofeeders. There is both a ground and tall version of the paleofeeder.
Different herbivores have different plants preferences and a variety is needed to fulfill the needs of various dinosaurs to their maximum extent. Since only one Greenhouse can be placed per island (aside from
Isla Nublar) players need to choose carefully which plants they intend to grow. Players can use the Plant Bed Upgrades to allow for additional plant slots.
The effect of feeding the preferred plants to a given species results in a bonus of up to 40% increased lifespan and rating. However, if harmful plants are fed to a given species, the detriments can result in a lifespan and ratings decrease of up to 25% and 50% respectively.