When to dig up dahlias?

Unfortunately, there comes a time when dahlias no longer bloom as beautifully as they did in summer. As winter approaches, it's time to lift the dahlia tubers from the ground. In this blog, we'll tell you when the time is right, how to do it, and how to safely store the tubers for winter. This way, you can enjoy beautiful dahlias again next year.

 

Why lift and overwinter dahlias?

Lifting dahlias from the ground is also known as harvesting. You do this when the first night frost has hit the plant and the stems have turned black or limp. Dahlias originate from warm Mexico and are not winter-hardy. By digging them up in time and storing them frost-free, you ensure that the energy the plant has built up this season is not lost.

The great thing? Next year, you can simply replant the same tubers and enjoy a full, flowering plant again!

 

What do you need for lifting dahlias?

Lifting dahlias is not difficult. You don't need much in terms of basic supplies:

• A shovel or spade to carefully loosen the tubers
• Pruning shears to cut the stems short
• A bucket or container to temporarily place the tubers in
• Newspapers or dry sand to pack the tubers for storage
• A frost-free storage place, such as a shed, cellar, or garage

 

When and how should you lift dahlias?

The right time to lift your dahlias is often after the first night frost. You'll usually recognize it by the stems! They'll turn black, limp, and the plant will look a bit defeated. That's an important sign. Don't wait too long after that, because the longer the tubers stay in frozen ground, the greater the chance of damage.

In the Netherlands, the first night frost generally occurs sometime between October and November, but this varies per year and per region. Keep an eye on the weather forecast as soon as temperatures drop towards zero at night.

 

Step by step: how to lift dahlias

• Step 1: Cut the stems back to about ten centimeters above the ground
• Step 2: Use a shovel or spade to dig broadly around the plant
• Step 3: Carefully lift the clump of tubers and shake off the soil
• Step 4: Let the tubers dry upside down for 2 days in an airy place
• Step 5: Wrap the tubers in newspaper and prepare them for storage

 

How to store dahlia tubers?

To enjoy dahlias again next year, it's important to store the lifted tubers properly. The best way to do this is in a frost-free, dark, and dry room. What can you consider? A shed, cellar, or garage where the temperature remains between five and ten degrees is fine.

Too cold and the tubers will freeze, too warm and they will sprout or rot. Place them in a crate or container with dry sand, peat moss, or newspaper around them, so they don't dry out and don't touch each other.

 

Can you leave dahlias in the ground?

Technically it's possible, but we almost never recommend it in the Netherlands. Dahlias are not winter-hardy and cannot survive a severe frost period in the ground. The tubers will freeze, rot away, and will not be usable next spring. If you want to be sure that you can enjoy the same plant again next year, then lifting them is the safest choice.

 

More dahlias in the garden?

Choose topping. Topping is perhaps the easiest way to get more out of your dahlias. One small intervention at the beginning of the season, and your plant will branch out instead of growing straight up. The result is a full dahlia that continues to bloom throughout the summer. We recently wrote an extensive blog about topping dahlias.

 

The risk of leaving dahlias in the ground

The biggest risk is freezing. As soon as the ground freezes deeply enough, the tubers will be damaged. They will freeze from the inside out, which you will only notice in the spring when nothing sprouts.

A second risk is rotting. Wet, cold soil in combination with the dead stems attracts mold. Tubers that survive the frost can still rot away before spring arrives.

 

When do you plant dahlias again?

As soon as the chance of night frost is over and the ground has warmed up sufficiently, it's time to plant your dahlias again. In the Netherlands, this is generally from mid-April to mid-May, depending on the weather. If you have stored the tubers well over the winter, you can simply replant them! We recently wrote a blog about the ideal period for planting dahlias.

 

Still need new dahlias?

Choose quality. Did you accidentally leave the dahlias in your garden for too long, or did the tubers not survive the winter well? No worries, at Bulbs4You you will find a wide range of over 250 dahlia varieties, directly selected from growers in the Bollenstreek.

You can easily order them online and we will deliver them neatly to your home, ready to plant as soon as the ground has warmed up again.