#HMIS129 Model #5920 Acadia planting instructions Drainage Holes: Depending on the intended use of the planter, drainage holes need to be drilled in different locations. Option #1: To utilize the water reserve feature, drill calfskin (8.8mm) radiometer hole where: the indentation Js shown an: the poster below. The overflow helps maintain idea water revels and ovoid over saturation of the doll.