Growing Dahlias: Trimming and Staking

This is an exciting day! I'm here with an update on my adventure in growing dahlias! Today I'm going to show you how my 27 tubers are doing and let you know what's next for the dahlias I'm growing.

Growing Dahlias: Trimming and Staking

As I mentioned in my first post in this series, I'm a novice at growing dahlias. This is my first official year growing dahlias in my backyard garden. (Last year I put a few tubers in pots, but I'm not sure that counts.) I planted 27 tubers (details on the varieties can be found here) this year, and I'm happy to report that all of them have sprouted! To be more precise, 25 sprouted, and I needed to plant 2 additional tubers. So technically speaking, 27 of the 29 tubers I planted are growing. Not too shabby for a newbie dahlia gardener! Here's a peek at how my garden looks right now:

Not bad, right? As you can see, there is some variance in the height and growth of the plants. That's because different varieties of tubers have different germination times. I noticed that the varieties I planted needed from 2 to 5 weeks to germinate. Once everything is growing, it's time to do a couple of things. The first is staking; the second is trimming or pinching.

Growing Dahlias: Staking

Dahlias grow tall and have large blooms. Thus, they need support as they grow. I decided to use cedar stakes and garden twine (both from Lowes) to support my dahlias.

It's important not to damage your tubers when adding the stakes. The best way is to insert the stakes in the soil before planting your tubers. Since I didn't do this, I had to wait to put in my stakes until after all of my tubers had started to bloom. That way I knew exactly where each tuber was planted. For my 27 dahlia plants, I used 18 cedar stakes. I then took garden twine and created a grid between all of the stakes. To avoid damaging the plants, a soft rope or garden twine is best. (This twine is similar to mine.) As you can see in the photos, I created two rows (or levels) of twine. This will offer twice the support as my dahlias grow.

Although I think my grid will be sufficient, I might create extra support by running garden twine diagonally between the stakes. Again, I'm new to all of this, so if you have suggestions, please let me know. Other Staking methods: From my research (and my limited personal experience), I've learned there are other staking methods to consider.

1. Cage/Trellis - Last year, I planted my tubers in large terra cotta pots. For support, I added a cage to each pot. (I found mine at Lowes, but these are similar.) The cages provided excellent support.
2. Grid System - You can also purchase a grid system like this one to support your blooms.
3. Single Stake - Another option is to put a stake next to each dahlia once it gets large enough. You can use garden twine to attach the plant to the stake.

I hope these additional ideas are helpful. Okay, now that your dahlias have been properly staked, it's time to talk about trimming.

Growing Dahlias: Trimming

It doesn't matter who I consult or what I read, everyone recommends trimming or pinching dahlias in the early stages of their growth. It seems counterproductive to cut the top off the plant, but doing so encourages branching, which will give you a fuller plant and more flowers! That's the goal, of course! And don't worry. At this point in the dahlias' life cycle, they are sprouting and growing rapidly, so they will recover quickly.

When to Trim Dahlias?

You want to trim off the top of the dahlia when the plant is about 16 to 18 inches tall. There should be at least four sets of leaves by then. Pinch or cut the center growing tip right above the fourth set of leaves.

It's that simple. Again, this will help you create a stronger plant with more blooms. It can keep the plant from becoming top-heavy. Win-win! And that's it! All that's left is for the plants to grow and bloom.

Growing Dahlias: More to Come!

If you're wondering about fertilizing and pest control, I will discuss that in my next growing dahlias post. I'm still testing different methods and products. I promise to share what I learn. Once I have a few blooms, I'll also offer information on cutting, deadheading, and such. But I can tell you now that the more blooms you cut, the more the plants will grow. Which is another reason to love dahlias! In case you have any questions, please let me know in the comments below! I hope you find this series of posts helpful should you decide to also grow dahlias. For me, this adventure has been filled with much joy and learning. I can't recommend it enough. Here's to LOTS of beautiful blooms!