Planter Box

Planter Box is used to grow plants from seeds that can be found in your world either by digging up or harvesting pre-existing plants, or by digging up a Buried Object. Using a Planter Box decreases growth time compared to natural growth, but requires additional care.

Mechanics

Plants that require irrigation can be planted in a Planter Box. Duplicants will provide the necessary liquids from a Pitcher Pump. Irrigation cannot be provided by a pipe.
For plants that require fertilizer it can be provided by Duplicants or automated by Auto-Sweeper.
A planter box can hold three cycles of irrigation and fertilizer for the plant it contains. For example if Mealwood is planted the box holds 30 kg of dirt. If Bristle Blossom is planted it holds 60kg of water.
When stored resources fall below what is required for 1/2 of a cycle, the planter box will request additional supplies.
Can't grow Thimble Reed nor Pincha Pepper.

Tips

Farm Tiles function identically to Planter Boxes. They are an upgrade because they can replace the floor and do not have a Decor penalty.

However, Planter Boxes also have advantages over Farm Tiles:

Planter Boxes can be built on top of Tiles that increase the Duplicant runspeed - whereas Farm Tile do not.
Planter Boxes can be built on top of Airflow Tiles that allow gas exchange - whereas Farm Tile block off gas exchange.
Planter Boxes can be built in front of Tempshift Plates and Drywall - whereas Farm Tiles cannot.
Planter Boxes don't block liquid. Wheezeworts become useless when their bottom tile is submerged in even a tiny amount of liquid, which could easily happen when Steam is cooled and turns into water. Thus the planter boxes can ensure that the Wheezewort stays active when cooling in steamy environments, without requiring constant duplicant mopping.