No Dig Dahlias

Dahlias are so GORGEOUS.

But can be so difficult to dig and store!

But good news! There is another way.

The tricky thing about dahlias is that they are basically a potato. A fleshy tuber that is very susceptible to freezing and wet soil.

To combat this most gardeners and flower farmers dig their dahlia tubers up at the end of the season.

They store them in ideal conditions and hope they don’t rot. Even for pros there can be a lot of loss.

Some tubers store better than others. Buildings that you thought were insulated well enough against frost, freeze. The humidity is too low and the tubers shrivel, and more.

It is a fraught system.

And honestly, if I had to dig and store all my dahlia tubers each year I would be reluctant to grow them.

Fortunately, there is another way!

In our growing zone, 7a, (and probably colder zones) you can leave your dahlia tubers in the ground.

You just need to follow a few steps to protect your tubers and then you are all set

Two Cornell Dahlias the morning after a hard frost.

After the first hard frost, cut back all the dahlia stalks and foliage. It's fine to leave some stubble.

The next step is to gather lots of leaves, straw, or hay.

Be sure to check the source of your hay or straw. Crops treated with a persistent herbicide will leech herbicide into your soil.

This will damage your soil and make it harder for your plants to grow for years to come.

You can avoid this by asking the person who is selling it if persistent herbicides were sprayed on the hay or straw.

Conquering the leaf pile.

Leaves are my go-to. They are free, abundant, and less fraught with chemical concerns. They are also the gold standard of soil amendments.

I check the calendars of the counties around me to see when leaf collection days will be. In the days before each pick up I head out with my truck and fill it up with bags of leaves. I even wrangle my husband and father in law into grabbing bags for me.

The gold standard of bed prep is to do a soil test in August. And then apply the needed amendments to the bed after analyzing the results.

But if you haven’t done that do not fear. Consider adding a general purpose organic fertilizer to the beds now.

Next add the leaves to your Dahlia beds.

Some folx like to mulch their leaves up first by running them through a lawn mower. That way they will break down more quickly the following year.

Layer the leaves about a foot thick. This will insulate the soil and keep the soil that the tubers are in from freezing.

The leaf jumping is all part of it.

If you’re into that!

Put a tarp on top of the whole bed. It looks unsightly but remember the end goal!

BEAUTIFUL, easy dahlias next year.

Be sure to stake the tarps down, even light winds can lift them off without reinforcements. You can use whatever you have to hold them down: bricks, rocks, sand bags, etc.

Remove the tarps in early April when the temperatures start to get more stable. Often there will already be visible growth.

You will have perennial dahlias, and thus have blooms much earlier. I usually have the first blooms in June with this method.