Dried out Dahlia tubers during winter seasons are often dead and unable to produce new shoots. They are also notoriously difficult to identify and separate from healthy plants.

How To Tell if Dahlia Tubers Are DeadOur aim is to provide you with some clear cut ways by which you can easily tell if your Dahlias are dead. So what are you waiting for, jump right in and find out now!

The Dahlia Tuber Plant

Dahlia tuber, like its sister species chrysanthemum and Zinnia, is one of the most diverse species of flowering plants. It is native to tropical regions like Mexico.

When the plant grows, it produces potato-like tubes along with elegant, beautiful flowers. Its flowers are beloved all over the world and this plant is also popular as an ornamental species in regular households.

Here is a list of important basic requirements to make this plant happy and healthy:

  • This plant likes to grow under full, direct sun conditions throughout the day. At least half a day of direct sunlight is a must. Otherwise, spindly plants with a low yield of flowers will appear.
  • It is best to use a soil that is rich in compost and manure. We also like to fertilize our soil prior to planting Dahlias in it.
  • After planting Dahlias in the ground, don’t water them until new shoots sprout from the ground. Doing so will lead to development of rot. After shoots grow, resume a regular watering regimen.

Dahlia Tubers

Dahlia tubers are a very sensitive type of plant. They are easily susceptible to succumb to a variety of problems including bacterial and fungal diseases as well as pest and bug attacks. They also cannot tolerate the winter frost and often die during the colder months of winter.

If you want to grow these beautiful flowering plants year after year in your garden, you must remove these tubers from the ground, dry them thoroughly, and then store them for replantation later in the season. 

How To Tell if Dahlia Tubers Are Dead

Dahlia tubers that are dug out before the winter frost hits your garden are often in a very bad shape. They look like they are dead and unlikely to sprout new roots

However, even a tiny viable part of the plant left in the tubers can lead to new growth. This is why it is imperative to know if the dried Dahlias you have are dead or alive so you don’t end up storing the dead ones and discarding those that are still viable.

Given below is a list of some of the most common signs exhibited by dead Dahlia tubers.

– Unpleasant Odor

Sometimes, all you have to do is smell these tubers to tell if they will sprout fresh roots in the upcoming spring season or not.

Gardener sorts out dahlia tubersNormally, Dahlia tuber flowers aren’t scented. The leaves and stem of this plant, however, give off a fresh, bittersweet fragrance when healthy.

A dead tuber, on the other hand, will definitely not emit a fresh smell at all. Most dead Dahlias are susceptible to fungal rot, ao you might notice a rotten, pungent smell coming from them indicative of fungal spores.

Sometimes, the dead Dahlias give off a very sickly-sweet foul smell. This is also indicative that the plant is dead and is now going through the process of decomposition.

– Squishy Texture

Texture can tell you a lot about whether your plant is alive or not. Simply hold it in your hands to evaluate its status. Healthy Dahlia tubers should feel firm and fleshy to touch, just like a freshly dug potato. If your tuber feels soft and mushy or has a squishy texture, then it is definitely dead or dying.

These mushy tubers have too much moisture stored in them. They are extremely prone to getting fungal rot, and these soft tubers will also show signs of concurrent diseases.

– Covered in Mold

A fungal infection is never a good sign for any plant. This is even more true for the overly sensitive Dahlia plant. One of the most common reasons why Dahlia tubers die is attack by fungal pathogens. Overwatering is the number one cause why your tuber might develop a fungal infection, since this plant needs to be watered only when the soil becomes dry.

If the drainage of your soil is poor and it tends to retain moisture for long periods, this too can lead to Dahlias developing fungal molds. You will notice brown or white mold covering some or most of the surface of these tubers. In severe cases, entire tubers might become rotten and black in appearance.

If the fungal mold is confined to the leaves in the form of white patches or brown spots, there is still time to save your plant. But if the tubers themselves are covered by mold, then your plant is more often than not already dead. If you find mold all the way to the neck of the tuber or through the crown attached to the tuber, then this tuber is also unfortunately dead.

– Brown and Dry

Did you know that Dahlia tubers dried out completely is also indicative that your precious plant is dead? Continue reading to find out how.Dahlia tubers on green grass

  • A Dahlia tuber looks uncannily like a potato. They have an elongated shape and are tan-colored. 
  • When you cut through a healthy tuber, the knife blade should pass smoothly through its body. You will also notice that although it is firm, it does retain some moisture in it.
  • A dead Dahlia will instead appear brown and dry. Even after cutting through it and crushing the cut portion, you will not be able to extract any moisture out of it.
  • Similarly, brown spots or the entire tuber turning brown is also a sign of a dead tuber.

How To Divide Dahlia Tubers Properly

– When To Divide Them

Leaving Dahlia tubers in the ground over the winter months is very risky, since this is the time when they are most vulnerable to infections and pest attacks. If you live somewhere that experiences even mildly cold winters, the frost will definitely kill your Dahlia tubers.

We suggest that you dig out your Dahlias at least one month before the onset of winter, then allow them to dry until spring. Divide them right before planting in early spring.


– How To Divide Them

Dividing Dahlia tubers is super easy and fun. Read the step-by-step guide we’ve outlined below to do this successfully.

  1. First of all, carefully dig out the entire Dahlia root system very carefully from the ground. It is very easy to damage the plant during digging to the point where it is incapable of sprouting any new roots.
  2. Start digging at least one foot away from the center of the plant. After lifting it off the ground, use a water spray to wash away the dirt and soil from it.
  3. Find the mother tuber amongst them and discard it. This is not going to be a viable plant in the future. Also, get rid of all the tubers that you deem dead or diseased.
  4. Always use clean and sterilized shears to divide the tubers.
  5. The next step is to find swollen eyes on each tuber. A tuber will not regrow unless it has at least one eye. These eyes can be seen at the top of the tuber.
  6. Sometimes these eyes aren’t clearly visible and you will have to put the tuber in a moist, warm area for several days until they appear.
  7. You can dust the cut parts with sulfur to prevent bacterial contamination.
  8. Your tubers are now ready to be planted into the soil.
  9. Water them appropriately. In a few weeks, fresh new sprouts will emerge.

Dahlia root system


Why do my Dahlia Tubers feel spongy?

Dahlia tubers may feel spongy due to rot caused by excessive moisture or fungal infections. Proper drainage and careful watering can help prevent this issue.

How do I know if my Dahlia Tubers have gall?

Look for swollen, distorted growths on Dahlia tubers to identify gall, which is typically caused by bacterial or fungal infections.

How do I know if my Dahlia Tubers have nutrient deficiencies?

Signs of nutrient deficiencies in Dahlia tubers include yellowing or browning leaves, stunted growth, and poor flowering. Soil testing can provide accurate nutrient recommendations.


In this guide, you learned how to distinguish dead Dahlia tubers from viable ones. You also learned how to divide them properly before replanting them every spring. Let’s quickly recap all of this information.

  • You can tell that a Dahlia tuber plant is dead by checking its odor. A foul-smelling plant is definitely non-viable.
  • A dead Dahlia tuber plant will lose its firmness and become soft and squishy in texture.
  • If you see fungal mold on the surface of these tubers, this also means that they are dead.
  • Sometimes, dead Dahlia tubers present as dry and brown-colored tubes
  • You should dig out these tubers from the ground one month before winter starts.
  • Allow them to dry over the winter and divide them at the beginning of spring.
  • Your tuber should have at least one eye or it won’t regrow in the spring.
  • Don’t water the newly planted Dahlias until shoots emerge from the ground up. Otherwise, your plant will develop fungal rot.
  • Remember that Dahlias prefer to grow under full, direct sunlight for the majority of the day. At the very least, half a day of sun exposure is a must.

The next time you plan to divide these tubers in the spring, we’re pretty confident that you will definitely know which ones are already dead!

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