Growing Guide: How to Grow Dahlia Tubers

A summer garden is not complete without Dahlias. These beautiful flowers, native to Central America and Mexico, are bold and vibrant perennials that are easy to plant and maintain, and perfect as cut flowers. However, if you are new to gardening, you may be wondering how to grow Dahlias. Don't worry, because we're going to explain it to you in this article.

1. Before You Get Started

Meet The Beautiful Dahlia Varieties

Before you start planting Dahlia tubers, you, of course, you need to decide which varieties to grow. We've put together a list of the main varieties and their characteristics.

• Single Dahlia: Single Dahlias, such as Dahlia Tricolore, have a single layer of rounded or pointed petals surrounding a central ring. Single Dahlias are known for attracting pollinators.

• Anemone flowering Dahlia: These Dahlias (Powder Puff Dahlias) bloom in distinctive double-feathered petals and are guaranteed to make a statement in your Dahlia garden.

• Cactus Dahlia: The Cactus Dahlia (Spiky Dahlia), such as Dahlia Table Dancer, has double-pointed petals that create a tube-like effect. They range in size, starting from miniature to giant sizes.

• Dark-leaf Dahlia: Dark-leaf Dahlias are known for their dark foliage. If you want to add some contrast to your garden, this is a good choice.

• Dwarf Dahlia: Dwarf Dahlias are small. However, they can still make a big impact, especially when planted in the front of garden borders and added to pots.

• Pompom Dahlia: Pompom Dahlias, such as Dahlia Burlesca, have sphere-shaped petals that curve inwards, creating a circular flower head.

Are Dahlias Perennials?

Dahlias are perennial plants that can return year after year. Do you live in a colder climate? If so, you need to help the plants. Dahlia flowers are very sensitive to the first fall frost and are not hardy in freezing conditions. You must dig up the best flowering tubers and store them for the winter.

2. Preparations

When To Plant Dahlia Tubers?

The planting time is everything when it comes to Dahlia tubers. The best time to plant tubers is in the spring, directly after the last whispers of winter frost have disappeared. Planting them at this time will ensure that they sprout before the summer heat arrives, maximizing their potential for a vibrant and successful blooming season.

How Deep To Plant Dahlia Tubers?

When it comes to planting Dahlia tubers, depth and spacing are key factors in ensuring your flowers thrive. Once the winter frost has disappeared, it's time to dig. Make holes about 4 inches (10 cm) deep in well-drained soil to prevent the tubers from rotting.

Learn more: When Is The Dahlia Blooming Season?

3. Planting

How To Plant Dahlia Tubers?

It’s time to plant the Dahlia tubers. Follow the instructions below to plant them in your garden:

1. Once the winter frost has disappeared, dig holes about 4 inches (10 cm) deep and 15 inches (38 cm) apart in well-drained soil. Dahlias prefer a full-sun location, so try to find a spot that receives plenty of sunlight throughout the day.

2. Plant the Dahlia tuber facing upwards with the tip of the tuber sticking out of the soil.

3. Water generously after covering the tuber with soil, and then add a fertilizer every few weeks to help the Dahlias grow during summer.

4. Pruning is not necessary with Dahlias, but you may want to deadhead the plants when some flowers begin to fade.

Grow Dahlias In Containers

Some gardeners like to start the Dahlia flowering season by planting the tubers in pots or containers. The process is similar to the instructions above. First, make sure the danger of frost has passed. Begin by placing a layer of pebbles at the bottom of your pot or container to improve drainage. Next, fill the pot with compost, position the tubers, and follow the previously described steps to grow stunning Dahlias.

4. Ongoing care

How To Take Care For Dahlias From Tubers?

To enjoy the vibrant colors of your Dahlia plants for as long as possible during the summer months, it’s important to take care of your flowers. Follow these techniques to extend the Dahlia flowering season.

• Deadheading: Regularly remove spent flowers. This simple step encourages the plant to focus its energy on producing new flowers.

• Pruning: Pinching the tops of young Dahlias when they reach about 12–18 inches (30–46 cm) promotes a fuller, bushier plant.

• Fertilizing: Dahlias are nutrient-hungry plants. Use a balanced, water-soluble fertilizer or a slow-release granular option to provide essential nutrients throughout the growing season. Follow the manufacturer's instructions for application rates.

• Mulching: Spread a layer of organic mulch around the plants to improve soil drainage, suppress weeds and keep the soil temperature consistent. Use pine straw, straw, or wood chips.

• Providing support: Most Dahlias create heavy, beautiful blooms that can cause the stems to bend or break. To prevent this, stake Dahlias to support their upright growth.

• Pest control: Keep an eye on your plants and take action if necessary to control pests. Prevent the plants from becoming prey for pests such as aphids, slugs, or spider mites.

5. Aftercare

Store Them During The Winter

Dahlia flowers are very sensitive to frost, especially if you live in a cold climate in the North of the US. Therefore, it is best to store the best-performing plants to prepare them for the next growing season.

1. Cut back stalks: Leave a stump 3 inches (about 7.6 cm) long, so a couple of inches (centimeters) remain above the ground.

2. Dig up the tubers: Lift the loose soil with the shovel or fork, grab the stalk and scoop up the bulb, carefully lifting the whole unit from the ground.

3. Examine and trim the tubers: Inspect the tubers and remove all the rotten parts. Shake off any excess dirt and trim back the root hairs.

4. Optional: divide tuber clumps: Use a clean knife and cut the individual tubers. Allow the “wounds” to dry and create a callus before storage.

5. Store the tubers: Store the tubers in a dark, cool location with good air circulation and moderate humidity. A basement, shed or garage with a temperature of 40-50ºF (4-10°C) is a good spot.

6. Check the tubers: Remove any rotten tubers during the storage period to prevent them from infecting the other tubers.

7. Replant in spring: When the dark, cold and freezing winter months are over, you can replant your Dahlia tubers.

For a more detailed description, follow the steps in our guide ‘How To Store Dahlia Tubers Over Winter’.

Discover the Dahlia Collection At DutchGrown

Are you ready to plant Dahlia tubers in your garden or containers and want to buy Dahlia tubers? At DutchGrown, you will find a beautiful, high-quality collection of Dahlia tubers. Whether you prefer soft pastel pink Dahlias or a variety with vibrant orange petals. Discover our stunning Dahlia collection now and start planting in spring. We ship from Holland to all over the US.