Storing your tubers
Dahlia tubers can be stored in a number of different mediums – potting mix, saw dust, cocopeat (coconut fibre). We have trialed all on our farm and all have worked well. Currently, we are storing our tubers exclusively in potting mix which is working well. It doesn't need to be expensive potting mix, as the tubers are not getting nutrition from it over winter.
If you are buying our tubers, they will come in a paper bag with rice husks and potting mix in them. We like this system because it means we can avoid plastic packaging. However, it is not designed for long term storage. On receiving any tuber, make sure you take it out of the packaging and inspect it before storing.
We recommend you put the tuber in an open lidded container ( e.g. a pot, an icecream container etc) and cover it completely with potting mix. If it’s a new bag of potting mix you most likely won't need to add moisture. If it’s an open bag that has dried out you may need to add some water until it feels cool, but not wet. Store in your garage/shed (frost free area) until planting.
Becoming good at storing tubers is definitely something that requires practise and needs to be adapted for each situation.
What makes a good tuber?
What does a tuber need to grow? It needs to have a body, a neck and an eye.
The colour of eyes can vary. They can be red, green, white or purple. Some say this correlates to the colour of the flower, but we have found too many exceptions to make this a rule!
The neck is often the skinnier part coming out from the central stalk and then the tuber widens into the body. Some tubers don’t have much of a neck at all. At the end of the body you can find the root or 'tail'. We cut these off for ease of storage, shipping and planting. Cutting off the tail also allows you to check for any hidden rot that may be in the tuber but not at first apparent.
Tubers come in all shapes and sizes, sometimes they are long and skinny. Other times they are short and fat. The size and shape doesn’t matter.
If you’re purchasing tubers you will most often receive a single tuber, already divided from the clump and ready for planting. On our farm we plant single tubers just like the ones we post out to our customers.
Learning to spot the eyes is definitely a skill, especially when they’re dormant. Often they look like a tiny pimple although if they’re very dormant you may not be able to see them. We double check all tubers before posting out for eyes. You can try to ‘wake up’ your tubers by putting them in some slightly damp potting mix somewhere warm to encourage them to sprout.
Unlike bulbs, Size DOES NOT matter with dahlia tubers. Tubers the size of a AAA battery or larger will grow into a full sized, healthy flowering plant in a single season. Dahlias grown from seed, cutting and tuber will all grow into a full sized flowering plant in one season.
We prefer smaller tubers at the farm as the plant has a smaller amount of reserved energy to rely on in the tuber. It has to establish it’s own, new root system faster than if it had a large tuber with lots of stored energy. Tubers that establish a root system faster will more resilient. Some growers will intentionally cut off the back half of a large tuber to encourage more root growth.
Help! I knocked off the eye/sprout!
It’s pretty easy to bump off an eye when you’re handling your tubers but it’s nothing to be worried about. The tuber will resprout.
The neck of a tuber is pretty important, its how the energy gets from the body of the tuber up to the eye to allow the plant to grow. Some peeled skin or a small cut in the neck often isn’t cause for worry, however if the neck is dried out and completely unstable, the tuber most likely won't grow.
Some superficial mould on tubers is quite common. Usually this doesn’t affect the viability of the tuber. Often you can just brush or wipe it off. You can also soak tubers briefly in a 10% bleach solution or spray them with vinegar. Just allow them to dry out before re-storing them.
Rot is usually caused by storing tubers in a medium which is too damp. Some varieties however are just more prone to rot than others no matter what you do.
Shrivelling, wrinkling and drying of tubers is a sign that the storage medium is too dry. Some drying out of tubers during storage is not uncommon and does not affect growth. We plant a lot of tubers with some degree of shrivelling on the farm every year with no issues.
Tubers are living things (even in their dormant stage) and sometimes despite our best attempts they don’t grow. If you are ever worried about the quality of tubers you have received contact your seller politely with your concerns. Include photos clearly showing your concerns. Chances are the tubers are not in the same condition as when they packed them.
Tubers often surprise me with their resilience and desire to grow. We plant mostly damaged tubers on the farm (as we've sold the good ones!) with no dramas.
You can buy dahlia tubers from our online store in the second half of each year – usually July-November some time. The opening date of the online store varies slightly each year. You can sign up to our email list to be notified about tuber sales as well as receive other helpful gardening advice.
If you’ve found this information helpful then please share this so that others can learn from it too. If you have a question that I didn’t answer please send me an email at firstname.lastname@example.org and let me know, chances are there are others who are wondering the exact same thing and I can include it in the FAQ section below for future readers.
Frequently asked questions:
- Can I store them in my house?
Yes. Just not somewhere too warm or humid. The bottom of the linen closet or laundry cupboard might work well. Make sure they have some airflow and check on them every now and then to see how they are storing.
- What kind of sawdust can I use?