I start with tap water. A small steady stream to dislodge any hitch hikers and I pull off any dead growth and debris at that time. This is followed by a dip in hydrogen peroxide. Procedures will vary and hopefully other chime in on this. I use it full strength. Place the plants in a zip lock bag or on a plate. Pour in some H2O2 and if using a plate, I cover that with paper towel. Let it sit for a few minutes. If you are planting right away then you don't need to rinse. Otherwise. A quick rinse with water should be fine.