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How to Grow Dahlias

Dahlias are a vibrant and beautiful choice for your garden. They are sown in spring, so you can see them flower through summer and fall. Dahlias need light and warm temperatures to grow, so it’s important to wait the winter frost out before you begin the venture. However, if you have access to a greenhouse, then it can be grown during the winters as well.

In a greenhouse, you can grow Dahlias by starting the growth of tubers. Once the frost period ends, and spring arrives, you can plant them in their designated flowering site. By growing them in tubers, you ensure that dahlias grow safely. Dahlias are very tender and cannot survive the cold or frost.  

Dahlias thrive during midsummer and throughout fall. They display colorful and attractive flowers throughout this period. The process of growing dahlias is quite easy, even if you’re a beginner.

The dahlia tubers flourish during the summer months and fall but will need to be stored through the winter to survive. They require a sunny location with fertile and well-hydrated soil for successful growth and flowering.

Are you ready to learn all about how to grow Dahlias? Let’s get started! 

Step #1: Choosing the Right Dahlia

Dahlias come in several shapes and colors, so that gives you a variety of flowers to choose from. Although choosing a dahlia is mostly about your own preferences, there are a few things that you need to keep in mind while picking your dahlia.

Keep in mind that dahlia flowers are usually classified and described by their shape. Some common examples include pompom, water lily, and collarette.

To help you make the right choice, take a look at the tips below:

  • For pollinators, single flowers are the best choice.
  • Large dinner-plate flowers are eye-catching, but they don’t blend with the borders well.
  • If you want to grow and cultivate the flowers in a container, then choose shorter cultivars.
  • If you want an economical way of creating mass color, then grow seed-raised dahlias.
  • Cultivars with dark-colored leaves can support the design of planting in borders.

What are the Different Sizes of Dahlias?

Dahlias offer a variety of size options. The short ones are called bedding dahlias, and they are a great option for the border front. Bedding dahlias are also an excellent choice for containers because they don’t grow taller than 2 feet (60cm).

Dahlias that are bigger in size require the support of skating to grow. They usually grow as tall as 4 feet (1.2m). The tallest dahlias can go as high as 6.5 feet (2m).

Step #2: Choosing the Planting Site for Dahlias

Here’s all that you’ll need for growing Dahlias:

  • Dahlia tubers: Buy as many dahlia tubers as you want to grow in your garden.  
  • The right planting site: Dahlias need sunlight, so you need to pick a spot that has access to direct sunlight for at least 6 to 8 hours per day. Try to look for a spot that is protected from heavy wind. 
  • The right type of soil texture: Dahlias grow the best in lighter soil. If you have heavy soil in your garden, such as clay, then add manure, sand, and peat moss to lighten and mix it up. Loose soil allows for better water drainage, and that’s what the dahlias need. 
  • Dedicated Pots: This tip is optional and only applies to large dahlias. Dedicated pots are perfect for growing large dahlias as they can grow freely without having to compete with other flowers. Consider growing a row of potted dahlias in the summer for a beautiful display of colorful flowers.

Step #3: Preparing the Soil for Growing Dahlias

After you have chosen the planting site for your dahlias, the next step is to prepare the soil. Dahlias require rich and light soil that is well-drained. You’ll have to ensure that the soil in which you plan on growing your dahlias is loamy, sandy, or acidic in nature.

In order to prepare a soil that is right for the dahlias, enrich it with rotten manure or compost. After that, add in a good mixture of fertilizer as per the instructions on its package. Before planting, dig deeper n the soil to loosen it, so it allows good drainage. Make sure you follow the instructions on the package for optimum levels of soil depth for your choice of dahlia.

Step #4: Planting the Dahlias

When you’re ready to plant the dahlias, make sure to eliminate the tubers with a rotten or wrinkled appearance. Choose the dahlia tubers with greenish or pinkish bud growths as they are the healthiest. Make sure that you don’t break dahlia tubers individually.  

When planting a row of bedding dahlias, keep them 9 to 12 inches apart from each other. The small-sized flowering plants that grow to a height of 3 feet should be around 2 feet apart.

Now let’s begin the planting process. Here are the steps that you need to follow for planting dahlias successfully:

  1. Dig a 6 to an 8-inch deep hole in the soil and set the dahlia tuners inside it. Make sure the growing points of the tubers are facing up.
  2. Now cover the hole with soil for up to 2 inches.  
  3. When the stem sprouts, add in more soil until it reaches the ground level.
  4. Make sure you don’t water the tubers before the sprouts have appeared because it will cause them to rot. Only water the sprouts when they have sprung above the soil.
  5. In the case of tall and big-flowered cultivars, place 5-feet tall stakes around the plants for support during planting time. Tie the stems of the plant to the stakes as they grow.
  6. Do not mulch the plants as they harbor slugs; dahlias like getting sunlight on the roots.

Final Words

On average, Dahlias take about 8 weeks to bloom after planting. They have beautiful and colorful flowers that will add beauty to your garden. The process of growing dahlias is pretty simple if you follow the steps. Make sure you keep the dahlias close to sunlight and away from cold and frost. 

If you have any questions or feedback about this tutorial, then leave them in the comments below!