Starting Dahlias Early Indoors

- Greetings from the Indoor Garden and welcome back to Let's Grow Stuff.

My name is Ben, and today, we're getting a jumpstart on the season, even though there is snow outside, by starting our dahlias indoors.

Let's get to it.

[upbeat electronic music] Dahlias are divas, and they will absolutely make a statement in your garden.

They're pretty easy to grow once you know the ropes, and they have been popular for decades thanks to their wide range of flower colors and forms.

If we have a slow, cold, cool spring, it can delay that flowering, which is why it's a benefit for us to start them indoors early to give us a jumpstart on the season.

When should we start dahlias indoors?

Give yourself at least six weeks before you plan to plant them outdoors.

Before you get started, make sure you have a good location indoors to grow your dahlias.

They need warm soil, at least 60 degrees Fahrenheit consistently, and they need as much light as you can give them.

So here's what we're starting with.

This is a dahlia tuber, and it sort of looks like a collection of little potatoes.

You either dug these out of your garden last fall or purchased them fresh this spring.

Before we plant them, let's inspect them to make sure they're healthy first.

Every dahlia has three parts: the tubers, the neck, and the eyes.

The tubers are these big, bulbous storage roots, and they come in all shapes and sizes.

Be sure all of your tubers are plump and firm, and discard any that are shriveled, squishy, or smelly.

The neck is where the tuber slims down, and so it's also where it's most delicate and can break, like this one did over here.

Finally, the eye is this little bump where this year's leaves and flowers will grow.

Besides your plants, here's what else you'll need.

Choose a peat-free potting soil and also, of course, your pots.

And you're looking for pots that are at least 6 to 10 inches across.

You can use either plastic or terra-cotta, and plastic are ideal if you're planning to plant them in the ground in your garden once the season warms up.

Terra-cotta is ideal if you're planning to put them on a deck or patio because they're gonna stay in this pot all year.

Fill each pot halfway with soil, then place one dahlia, stem side up, onto the soil.

Now we fill up the rest of our pot.

As you can see, last year's stem is still sticking up out of the soil just a bit.

And that's okay because this year's new growth is gonna come up from below that point.

You may be tempted to fill your pot all the way to the brim with soil, but don't do this because as you can see, if it was too full, this water would run out the side instead of getting into your pot.

Next, place your pots in a warm location and wait for them to sprout.

Plan to water when the top two inches of soil is dry or every 5 to 7 days.

What comes next is an epic tip that I learned that completely changed the way I grow my dahlias.

What we want to do is wait until each of our stems has a couple sets of leaves.

This plant still has a little ways to go before we reach that point, but when we do, we'll pinch off the top growing point right here on each of our three growing stems.

This forces the plant to create a sort of trunk at the base of the stem, effectively yielding dozens more flowers later in the year.

Now it's time to start thinking about getting our dahlias ready to go outside.

As we approach that final frost state for your region, we'll start to get them acclimated to the outdoors through a process that we call hardening off.

As a reminder, hardening off is a process which acclimates your plants to growing outside.

At the end of that period of time, they're ready to go outdoors full time.

Well, there you have it.

Our dahlias are off and rolling, and will give us many more weeks of flowers as a result.

Don't forget, there is so much more to learn online at letsgrowstuff.org.

There, we have more videos, tips, tricks, and a blog to help you grow a better garden.

So until next time, happy gardening.

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