Once a sapling is placed, it cannot be picked back up. However, placed torches will prevent tree growth, so do not place any torches within two tiles to the left and right of the sapling.
Light levels do not affect the growth of Gemcorns at all, therefore light sources can be placed nearby to help the player see better. The minimum requirements for a Gem Tree to grow is for it to be planted on one of two immediately adjacent Stone, Moss, or any of their biome variants at the Underground or Cavern layer, displayed by the Depth Meter.
Almost all background is covered with walls, except for the 2 tiles where the Gem Tree sapling occupies once placed. The floor is completely Stone, with non-painted blocks spaced by three black painted ones to mark optimal spacing and places without background.
