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There are a ton of resources out there that go over the ins and outs of digging, dividing and storing dahlia tubers. This is my way and does NOT mean you are doing it wrong, or that you should make a change - It’s just what works for me. I will update the dividing section once I have a chance to take some photos.

I start off by cutting back all of the plant material so that just a little bit of the stalk is showing…I have tried a TON of tools and last season I bought myself one of these electric pruners (my dad has since gotten 2 more of them for jobs around the farm and as a gift for a farmer friend who prunes A LOT of Christmas Trees every year at his tree farm). It has become by far a top 5 tool for me this season. If you are a small scale grower you don’t need fancy tools for five clumps - Keep in mind I grow thousands of dahlias - but it has truly been a game changer!

I usually dig my tubers using a 4 tine gardening fork. My soil is fairly clay-like and this works for me - you could also use a large garden shovel. I work my way all around the tuber clump, loosening the soil before lifting. If you are too hasty, the tubers will break, usually right at the neck (which will ruin them) or they will snap in half (not as bad but still can lead to storage issues).

I will go down a whole row at a time, making sure my labels and variety markings are super crystal clear, and dig and pull all the clumps out, laying them on solid ground to dry off a bit to leave as much of the soil in the field as possible. I’ll come back a few hours later and brush off as much soil as I can get off. I do NOT wash my clumps. They go straight into bulb crates and then into my cooler, with multiple labels on each crate in case something falls off or gets lost heading from field to workshop.

These guys had too much soil left on them but sometimes you gotta move fast!

One important thing to remember is you cannot place these crates directly on concrete. The moisture will get sucked right out of the tubers (overnight, literally). I put down sheets of insulation in my cooler and then put one empty crate at the bottom of each stack. Yes it takes a lot of crates! I aim to keep my cooler between 40-50 degrees which right now in November when it’s 77* is easy, but come Jan-Feb is tricky. A little space heater and air circulation helps - I run a fan and if I see any sign of mold from all the moisture from the soil and tubers, I may run a dehumidifier. Some people run humidifier - it just depends on your conditions. I have tried attic storage in the past and it was not ideal.

When it comes time to divide, I brush off the dried up dirt (it usually comes right off as it has had plenty of time to sit) and get to it. My favorite tool for this task are these Zenport scissors - They stay sharp and are strong enough to fight through even the biggest tubers.

Once divided, it is important to let the cut portion of the tuber heal and dry before putting them back into storage which at this point is plastic tubs full of vermiculite. I usually let them sit for 24-48 hours and then place them in their bins.

Now after all of this writing, I’m going to tell you (especially the local home gardeners who get tubers from me) - If you are in my zone or a bit warmer, you likely will have some success overwintering your dahlias. Cut them back, cover with a thick layer of leaves and if you are super on the ball, a layer of plastic - this would be to prevent too much water from getting to them and freezing them. Storing them is way harder than leaving them in the ground as the temp and humidity have to be right for them not to mold, shrivel, freeze, rot etc. The downside from overwintering is that if you decide to dig in a few years the clumps will be ginormous!

Happy to answer questions and I will post more photos of the dividing process once I get to it - soon, very soon!

Thanks for reading!