The next step in the propagation of Dahlia ‘Princess Marie José’ for the Plant Exchange saw me retrieving the tubers from their winter nest of shredded paper, laying them out in seed trays and covering with compost. I brought my propagator into the house to reduce the heating required and waited to see the shoots.
A month or so earlier, I had brought one of the pots of this Dahlia into the house thinking that I would get a head start with one of the plants. I would then be able to show the office members new to Dahlia propagation, how to proceed with their plants. A root appeared out of the bottom of the pot, but disappeared. A slug was found, disposed of and blamed for the slow progress. But when the propagator plants overtook the plant in the pot I began to wonder. Has the tuber rotted off, are there any roots in there? So I tipped out the compost and found……..two vine weevil grubs chomping away on the roots.
In my post of December I said that I would be testing the traditional method of storing tubers with Bunny Guiness’ method of keeping them in pots. My results indicate that although the pot-stored tubers produced shoots slightly quicker, the downside is the potential for vine weevil damage. So if the tubers are overwintered in their pots, I would suggest potting up in fresh compost.
I have now taken cuttings, (stem cut just below a leaf node and large leaves removed) which are in small pots and brought back into the house to keep them a little warmer and out of direct sunlight. The DIY propagator pots recommended by Brian Deaville at the Surrey group meeting in January are also being tested. I have cut the remaining tubers into two or more sections, each with at least one shoot, potted them up and these are under fleece in an unheated greenhouse. We will now wait to hear how many plants have been requested in the Annual Plant Exchange and hope that we can fulfill the demand.
We also had a mini workshop at National Office to give the ‘novices’ an opportunity to experiment with taking cuttings before they start on their ‘Princesses’.