The 10 x 20 Mesh Bottom Propagation Tray is a great add-on, making propagation more effective. Ensure proper drainage by sliding this mesh bottom plastic propagation tray into a standard 10 x 20 tray. This setup allows you to place your starter plugs (i.e. rockwool sheet of 98) inside the mesh bottom tray and allow the water to drain into the lower tray. for best results, hand watering is recommended. Mesh Bottom 10 x 20 Propagation trays are great for both horticultural hobbyists and professionals.