Stop dirt leaking out of your plant pots., Every time you water, soil spills out the bottom, So people try to plug the drain hole to stop the mess., Bad idea., That traps water in the pot which can Easy Slow Cooker Savory Pot Roast Amazon.com : PietyPet Fish Tank Accessories Green Plants, 10pcs Green Fish Tank Decorations, Aquarium Decor Plastic Plants : Pet Supplies Clay Pots vs. Plastic Pots Should You Use Clay Pots Or Plastic Pots Gardening Know How DIY Eco Friendly Plant Pot Ideas from Plastic Bottles Soil mix for cymbidium? : r orchids