Starting Dahlias In Baggies

When I prep them for storage I usually can’t tell where the eyes are, so before starting the tubers I usually first let them sit for a week or two at room temperature. I leave them bundled like they were in the fridge, so that they won’t dry out. I have some dark shelves at the top of my growing racks where I can set them, which gives them a bit of warmt from the lamps but not the light, so I just put a couple trays of them up there at a time.

This gives the eyes a chance to start forming stalks and makes it easier to pick out the duds. I try to avoid going much longer, though, because in the cramped bundles the stalk tips will eventually run out room and start rotting.

I start the tubers in sandwich bags. I use clear bags so that I can easily what’s going on inside with regard to root formation and moisture. I remove any ziplock-type connectors so that the bags will stay open more easily.

To allow drainage, I run a perforating tool along the bottom edge of the bag.

In that picture I also tried perforating the side to make it easier to remove the bag later on, but it turned out those perforations didn’t really tear and it was easier to just split open the seam on the edge of the bag. So now I only do the bottom edge.

Then it’s just a long process of unwrapping bundles of tubers, discarding the bad ones, and putting them into labeled baggies. I usually also write the date that I started them, so that I can more easily tell if they get stuck or are growing really slowly.

This Fired Up has a couple eyes sprouting, for example:

After setting them aside in bags, I add potting mix. I try to completely bury the tuber. Sometimes the end is sticking out in the air, which doesn’t really hurt growth but it can make them harder to plant later on since leaves and branches will form very close to the tuber.

Then I add a bit of water to make sure the mix is damp at the beginning, and the trays of bags go onto the grow shelves. I usually start them out under the fluorescent fixtures I have at the top of my racks since they put off more warmth. Every couple weeks I bag some more, move them around on the shelves, pull more bundles out of the fridge to start warming them up, etc.

For 2019 I started 136 over a period of about 7 weeks.