The #1 Mistake To Avoid When Splitting Dahlia Tubers
November 13, 2023
This past growing season, we grew over 1,700 dahlias in our flower field in Burt, NY Zone 6b. The majority of the tubers we planted were grown and split from our own dahlia tuber stock that we’ve been growing for the past five years on our flower farm. Every year after the first frost, we dig up our dahlia tubers, pack and store the dahlia tubers in our basement, and split (or “divide”) them into smaller pieces to either replant in our farm or sell in our annual Dahlia Tuber Sale.
Splitting dahlia tubers is a skill that can only be honed through practice (I know, because I’ve practiced). Splitting dahlia tubers can be done right away after digging them up, or you can wait until later to split your dahlia tubers right before planting. You can use a variety of tools to aide in splitting your dahlia tubers — strong floral snips are my favorite tool to use to split dahlias. Sometimes I’ll even bust out the hammer and chisel to break apart those really big, compact clumps (I’m looking at you, Center Court).
There are a few golden rules to follow when splitting dahlia tubers: Try not to break the neck, always make sure an actual growing eye is attached to the tuber, and your tubers should be a certain size (not too big, not too small).
However, there is one golden rule of splitting dahlia tubers that you must follow above all, and that is making sure your dahlia tuber splitting tools are SANITARY.
The #1 Mistake to Avoid When Splitting Dahlia Tubers
You must must must disinfect your tools in between splitting every dahlia clump! This is the most important rule! Do not make the mistake of splitting all of your dahlias without cleaning your tools in between every clump.
Why is sanitation so important when splitting dahlia tubers?
If you don’t disinfect your tools between every clump, you could potentially spread diseases such as dahlia crown gall and dahlia leafy gall. I know this to be true because I’ve unfortunately done this! In the past, I have devastated half of my dahlia tuber stock because I did not know to sanitize my tools in between clumps. So heed this warning: If you don’t disinfect your dahlia dividing tools, you are putting your entire collection at risk.
what are dahlia tuber diseases?
The most common dahlia tuber diseases are crown gall and leafy gall. Please refer to this blog post if you want to learn how to identify dahlia gall and what to do about it.
how to sanitize dahlia splitting tools
There are two things you can use to sanitize your dahlia splitting tools: 70% Isopropyl Alcohol (rubbing alcohol) or Bleach.
I prefer using rubbing alcohol to sanitize my tools simply because I don’t enjoy getting bleach all over my clothes. The process is incredibly simple and painless. I dump rubbing alcohol into a small vase (something that won’t easily tip over) and in between every dahlia clump I submerge my snips in the alcohol (the snipper parts that touch the tubers only), for 10 seconds before moving onto the next clump. I use two pairs of snips and rotate back and forth between the two pairs so there is always one pair sitting in the alcohol.
Sanitizing tools is such an important part of working with plants, and a step that is easily overlooked. Sanitation is not only important for splitting dahlia tubers — it is also important for starting seeds, propagating plants and even arranging flowers!
peace, love, and the cleanest of snips this splitting season,
Fran Parrish
