Preparing to be Dazzled by Dahlias20th February 2018 • In The Garden • Daniel Carruthers
If, like me, you dig up your dahlias and store them overwinter – or have bought some new tubers – now is the time to get them potted up and growing-on. Stored dahlias should be removed from whatever you have stored them in (I use newspaper lined crates of spent compost) cleaned and tidied, checked for any damage or rot and then potted up into fresh compost. Give them a good soak and stand them in good light in a greenhouse, cold frame or other frost-free place. I’ve mulched my dahlias with Strulch to stop the compost drying out and have put a couple of slug pellets in each pot.
Slugs love young dahlia foliage (this is why I’ve stopped leaving them in the ground – I got fed up with them being chewed to extinction) so the pellets are insurance against any lurking slugs in the greenhouse. Once they are growing strongly I will reduce the number of shoots to five and pinch these out when they are 25cm tall. This will produce robust plants that flower well. Liquid feed the dahlias as they grow and plant them out once all danger of frost has passed. They will probably flower before then, which will be no bad thing for me as some of the tubers have become detached from their labels!