How to Clean Dahlia Tubers A Step-by-Step Guide for Healthy Winter Storage
Dahlia tubers are swollen stems that dahlia plants produce underground to store energy through the winter. Properly cleaning freshly dug tubers is a crucial step before storing them for dormancy. Removing all soil and debris prevents rotting or disease issues from arising during storage.
Follow this complete guide to learn how to thoroughly clean dahlia tubers after digging them up in fall
When to Dig and Clean Dahlia Tubers
Dahlias should be dug up in fall after the first light frost blackens the foliage. Avoid digging too early or the tubers may not be fully mature.
Ideally dig when:
- Plant growth slows down
- Stems begin dying back
- Days become shorter and cooler
This is generally 4-6 weeks before the ground freezes in your area.
Digging Up Dahlia Tubers
Use a garden fork to dig tubers, taking care not to stab or slice them. Dig about 12 inches away from the plant’s center and lift out the entire clump.
Shake or rinse off excess soil still attached to the clump. Cut stems back to about 2 inches above the top of the tubers.
Why Cleaning is Important
Thoroughly cleaning dahlia tubers right after digging serves several purposes:
- Removes soil that harbors disease organisms
- Allows inspection for damage or rot
- Prevents tubers drying out before storing
- Removes nesting spots for insects or rodents
- Improves storage by eliminating excess weight and bulk
Proper cleaning is a vital step in maintaining healthy tubers.
How to Clean Dahlia Tubers
Follow these steps to thoroughly clean dahlia tubers after digging them up:
- Wash the Clumps
Use a garden hose or bucket of water to thoroughly rinse the soil off the dahlia tubers. Spray or soak the clumps to remove all soil.
- Dry Upside Down
Stand the washed clumps upside down to allow water to drain out of the tuber crowns. Leaving them upside down prevents water pooling and possible rotting.
- Separate the Tubers
Once drained, carefully separate the individual tubers from the clump. Use a clean, sharp knife to divide them, sterilizing between each cut.
- Inspect for Damage
Check each tuber, discarding any with rot, significant insect damage, or other defects. Look for discoloration or soft spots that indicate rot.
- Wash Again
Give the separated tubers another wash to remove any remaining soil or debris. Use a soft brush to gently scrub if needed.
- Dry Thoroughly
Allow the clean, separated tubers to dry completely before storage. Lay them out in a single layer in a well-ventilated area out of direct sun.
- Label Varieties
Mark each dry tuber with its dahlia variety using a permanent marker. Proper labeling prevents mixing up types later.
Storing Cleaned Tubers
Once thoroughly dried, the cleaned tubers can be packed for winter storage:
- Place in breathable bags like mesh onion sacks
- Use slightly dampened vermiculite, peat, or wood shavings as packing material
- Store in a dark, cool (40-50°F) spot like a basement or unheated garage
Regularly check stored tubers, removing any that show signs of rotting. Proper cleaning and careful handling prevents issues from arising over the winter.
In spring, the tubers can be retrieved and replanted for another season of gorgeous dahlia blooms!
FAQs About Cleaning Dahlias
Should I use any disinfectants when cleaning tubers?
Most experts advise against using chemical disinfectants when cleaning tubers. The main purpose is to remove soil and debris rather than kill bacteria. Good airflow while drying provides enough disease prevention.
How can I avoid damaging tubers when digging?
Use a garden fork rather than spade when digging. Take care not to stab or slice into tubers. Dig at least 12 inches away from the plant’s center to avoid severing main tuber crowns.
Is it okay if some soil remains stuck to tubers?
It’s best to remove all soil through washing. Any remaining clumps provide places for insects or disease to establish. Be sure to thoroughly scrub off all soil.
Should I cut off sprouts or stems before storing?
Yes, trim stems down to about 2 inches above the topmost tubers. Remove any small sprouts as well. This prevents the tubers losing moisture through the stems and foliage.
What if some tubers are quite small?
Even tiny peanut-sized tubers can be saved. They may not sprout the first season after planting but can still grow into productive plants later on. Mark them separately so you don’t confuse them with sets.
Why shouldn’t tubers dry in direct sun?
The heat can actually cook tubers if left drying too long, causing tissue damage. Gentle shade drying prevents harming the tubers. Turn them periodically for even air exposure.
Thoroughly cleaning dahlia tubers is a simple process that pays off through healthy tubers and bountiful blooms for years to come. Follow these tips to properly prep your tubers for winter hibernation.
How To Clean & Wash Your Dahlia Tubers For Winter Storage
FAQ
How do you clean dahlia tubers?
Use a hose or bucket of water to thoroughly rinse the soil off the dahlia tubers, and then stand the tubers upside down to dry.
Are shriveled dahlia tubers still good?
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Signs of a viable tuber:
- Firm and pliable: A healthy tuber should feel firm but not brittle or hard like a rock.
- Plump and smooth: A healthy tuber should have a smooth surface and be plump, not shriveled or wrinkled.
- Visible eye/crown: Look for a visible eye or crown on the tuber, which is where new growth will emerge.
- Strong, sturdy neck: The neck connecting the crown to the body of the tuber should be strong and sturdy.
- Firm and pliable: A healthy tuber should feel firm but not brittle or hard like a rock.
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Signs of a non-viable tuber:
- Soft, mushy, or slimy: If the tuber feels soft, mushy, or slimy, it’s likely rotten and should be discarded.
- Brittle and cracked: A tuber that is brittle and cracked is also likely not viable.
- Completely dried out and desiccated: If the tuber is completely dried out and desiccated, it’s unlikely to grow.
- Soft, mushy, or slimy: If the tuber feels soft, mushy, or slimy, it’s likely rotten and should be discarded.
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Troubleshooting shriveled tubers:
- Check storage conditions: Ensure your storage environment is not too dry. Dahlias prefer a cool, dark place with 40-80% humidity.
- Rehydrate tubers: If you have some shriveled tubers with some heft, try rehydrating them by placing them in a pot with dry potting soil in a sunny window until shoots emerge, then water sparingly.
- Consider pre-sprouting: You can try pre-sprouting tubers before planting to see if they are viable.
- Check storage conditions: Ensure your storage environment is not too dry. Dahlias prefer a cool, dark place with 40-80% humidity.
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When to discard:
- Rot or mold: If you notice any signs of rot or mold, discard the tuber immediately to prevent it from spreading to other tubers.
- Soft, mushy, or decayed: Any tuber that is soft, mushy, or appears decayed should be discarded.
- Rot or mold: If you notice any signs of rot or mold, discard the tuber immediately to prevent it from spreading to other tubers.
Why dip dahlia tubers in cinnamon?
Cinnamon is supposed to help keep them from molding.
What do you dust dahlia tubers with?
Tubers can optionally be dipped in a diluted bleach solution, or dusted with sulphur powder to prevent rotting. Typically, the tubers are then stored in a damp, clean material (like peat moss, shredded paper, or cedar shavings).
How do you divide a dahlia plant?
When you divide the tubers, it is important that each tuber has part of the original tuber stock along with a neck, body and eye. Without these parts, you will not be able to grow a new dahlia plant. I like to start by dividing my tuber clump in half. This allows me to get in and divide the tuber clump into individual tubers.
Can you divide dahlia tubers?
You can divide your dahlia tubers in either the winter or springtime. You may want to wait until spring when the tuber eyes are more visible. To get started you will want a clean workspace, a good pair of garden scissors, cinnamon, and bleach. I bleach my tools between each set of tubers to make sure I don’t spread any potential disease.
How do you store dahlias?
You can also store your dahlias in peat moss. Don’t store your dahlias in cardboard boxes as the cardboard will suck the moisture out of your tubers. You can divide your dahlia tubers in either the winter or springtime. You may want to wait until spring when the tuber eyes are more visible.
Should you dig up Dahlia tubers?
Digging up dahlia tubers is a tedious process. However, you will be rewarded with even more viable tubers for the following summer! Dahlia tubers are expensive. One of the best ways to multiply your stock is to dig up your tubers at the end of the growing season and divide them.
How do you remove a dahlia clump?
Dig and handle the clumps with care. A dahlia tuber’s neck is fragile, especially right after digging. To remove the clumps, dig on all four sides of the plant, about a foot away from the main stalk. When all four sides are loose from longer feeder roots, push the shovel or tined fork under the clump and lift carefully.