Chilli Growing Guide Deep Green Permaculture Pure Garden 20.75 in. Outdoor Plastic Railing Planter, Gray Danilo Planter, Extra Large Campania International Onyx Black Lite DIY Hanging Wood Wall Planter (Built in Under an Hour!)Wood Planter for the Wall Shanty 2 Chic Plant hollyhock seeds in pots, harden, then plant outdoors after last frost date It can be difficult to know which growing medium to use for your plants. We asked experts the difference between compost, potting soil, and topsoil to help guide your decision. See more