By now most dahlia tubers have been lifted through each of the cold garden zones. If you haven’t lifted your dahlias, hurry along for wintertime is coming.
Here at the farm the dahlias have been put away in storage for another winter nap in great anticipation for another season of growing.
Nothing is more frustrating or expensive than growing a crop of beautiful dahlias, harvesting the tubers and then falling short of storage precautions, which leads to a loss come spring inspection. I’ve been there in the early years of growing, but a gardener or flower farmer will soon find the proper storage method that’s appropriate for them and their storage space.
Have you had difficulty storing your dahlia tubers over the winter months? Allow me to share some tips with you. The ways I’ve done to prepare for a successful winter storage has been tried and proven to fit my particular needs/condition.
First and foremost, I prefer the dahlias to obtain a few good frosts to ensure that all foliage has died back. Keep in mind every gardener/flower farmer’s situation is unique and different.
After we dig our dahlia tubers, I like to go ahead and wash them, allowing them to dry completely for about four hours. You as a gardener or flower farmer may find it well to not wash them and that’s each one’s own preference.
When tubers are completely dry—and I highly emphasize dry—tuber clumps are placed into bulb crates or milk crates that have been lined with paper. Bulb crates and milk crates have been proven to be a good choice for storage due to the excellent air flow as this keeps tubers from rotting. However, if you use sealed plastic containers, I highly recommend adding holes to the container.
Some fall seasons we have time to separate the clumps into single tubers, but most seasons we don’t. Therefore, we fit them well into the crates giving them good air flow.
As we layer the bottom of each crate with tubers, a slight, fluffy layer of sawdust/horse manure is added. That’s what we use here at the farm since we have low humidity. If you don’t have access to the mixture we use here at the farm, try peat moss or vermiculite instead.
Your dahlia tubers will need to be kept in a cool, but not freezing environment, and they’ll require relatively high humidity. We always try to aim for 38-50oF and 75%-85% humidity. When storage temperatures are too low, you run the risk of freezing your dahlia tubers. Try your best not to go much past 50oF because the tubers will begin to wake prematurely. Be conscious of the humidity. If it’s too high, the tubers may develop mold and can rot. Mold can be a scary thing for it spreads rapidly if not caught in time. Too low humidity will cause tubers to dry out and dehydrate which can be one of the top failures in dahlia storage.
Ultimately, part of growing dahlias is the learning experience. You’ll find what works best for you. All your efforts will be rewarded when summer arrives, and your gardens will be filled with beautiful dahlia blooms!
Happy Gardening!
Pamela Anthony
Beehind Thyme Farm & Garden