The Eco and Pocket planters can safely be sprayed out and washed like normal. We recommend air drying and not stacking until completely dry. Eco planters are 100% dishwasher safe (we recommend top rack). For mineral buildup, we recommend using a shop vacuum. Pro tip for the Pocket: Vacuum any build-up out of the felt by saturating the front with water, then skimming the surface with a flat nozzle attachment.