CastleGreens Premium Black 20 Gallon Fabric Grow Pot w Handles Agricova How to pot up dahlias , If your dahlias have started to arrive you can begin to pot them up. I like to do this from late February Mid March. It gives me chance to check the viability of the tubers Estate 1 Gallon Lawn Garden Sprayer AUTMOON 98 in. Metal Garden Arch Trellis Assemble Freely with 8 Styles, Climbing Plants Support Wedding Archway, Black Succulent Arrangement Tiffany Trio of Small White Geometric Pots