Introduction
There is something deeply satisfying about watching a pom pom dahlia come into bloom. These flowers look like perfectly crafted spheres, featuring a neat, honeycomb-like pattern that seems almost too precise to be real. Adding these geometric wonders to your yard brings a sense of playful sophistication and texture that few other plants can match. Whether you are tucking them into a perennial border or dedicated cutting garden, they are a joy to grow from early summer until the first frost.
At Longfield Gardens, we want to help you experience the simple pleasure of a successful dahlia season. These plants are remarkably rewarding when you get the basics right. This guide is designed for home gardeners who want clear, practical steps to growing beautiful pom pom varieties. We will cover everything from choosing the right spot to the specific planting depths for dahlia tubers that ensure your tubers thrive.
Growing these petite, globe-shaped flowers is an achievable goal for any skill level. By following a few simple rules about sun, soil, and timing, you can enjoy a season filled with dozens of blooms. Our goal is to make the process easy so you can spend less time worrying and more time enjoying your garden. The secret to success lies in matching the plant's needs to your local environment.
What Makes Pom Pom Dahlias Special?
Before we dig into the planting process, it helps to understand what makes a pom pom dahlia unique. These flowers are known for their small, perfectly round shape. By definition, a pom pom dahlia must be less than two inches in diameter. This makes them significantly smaller than their cousins, the ball dahlias, which have a similar shape but much larger blooms.
The petals of a pom pom dahlia are "involute," which means they roll inward to form tiny tubes. These tubes create the famous honeycomb texture. Because the blooms are compact and the stems are typically quite sturdy, they are excellent at withstanding summer rain and wind. They are also heavy producers, often sending up more flowers per plant than the larger dinnerplate varieties. For a broader overview of dahlia forms and care, see this dahlia tuber planting and care guide.
Pom pom dahlias come in a wide array of colors, from soft pastels like lilac and cream to bold, saturated hues like deep crimson and bright orange. Because of their size, they are the darlings of floral arrangers. They add structural interest to bouquets and stay fresh in a vase for a surprisingly long time. Knowing these traits helps you plan where they will look best in your landscape.
Choosing the Best Location
Success starts with the right environment. Like most summer-blooming tubers, pom pom dahlias have a few non-negotiable requirements. If you give them what they need from the start, the rest of the season becomes much easier.
Prioritize Sunlight
Dahlias are sun-worshippers. To produce those intricate, nectar-rich flowers, they need at least six to eight hours of direct sunlight every day. Full sun keeps the stems strong and prevents the plants from becoming "leggy," which is when they grow tall and thin while reaching for light. If you live in an exceptionally hot climate, a little bit of dappled shade in the late afternoon can help prevent the petals from fading, but morning sun is essential. You can also browse Longfield Gardens' spring-planted flowers for sun.
Check the Drainage
Drainage describes how fast water leaves the soil after a rainstorm or watering. Pom pom dahlias grow from tubers, which are thick, starchy roots similar to a potato. If these tubers sit in soggy soil for too long, they cannot breathe and may rot.
You can check your drainage by digging a small hole and filling it with water. If the water disappears within an hour, your drainage is excellent. If it sits for several hours, you may want to plant in a raised bed or improve the soil. Adding organic matter, like compost, is a simple way to improve soil structure and help water move through it more effectively.
Provide Enough Space
Even though pom pom blooms are small, the plants themselves can grow to be three or four feet tall and two feet wide. Giving them enough room ensures that air can circulate around the leaves. Good airflow is a natural way to keep your plants healthy throughout the humid summer months. Plan to space your pom pom dahlias about 12 to 18 inches apart to give each one room to shine.
When to Plant Your Tubers
In gardening, timing often matters more than any special trick or tool. Because dahlias are native to the warm climates of Mexico and Central America, they have no tolerance for freezing temperatures.
Wait for Warm Soil
The biggest mistake gardeners make is planting too early in the spring. Even if the air feels warm, the soil takes longer to heat up. We recommend waiting until the danger of frost has completely passed and the soil temperature reaches about 60°F. If you have a compost or soil thermometer, you can check this easily. If not, a good rule of thumb is to plant them around the same time you would put tomatoes or peppers in the ground.
Consider Your Zone
We ship our tubers from Longfield Gardens based on your USDA hardiness zone. This ensures they arrive when it is nearly time to plant. If you receive your tubers and the ground is still cold or wet, it is perfectly fine to keep them in their shipping bags in a cool, dark, dry place like a basement for a week or two. You want the soil to be crumbly and workable, not muddy or cold.
Key Takeaway: Always wait for the soil to warm up and the threat of frost to pass before planting. Planting into warm, well-draining soil is the fastest way to get your dahlias off to a strong start.
Preparing the Tubers for Planting
When you open your package, you will see a cluster of tubers that look a bit like a bunch of carrots or sausages. Each of these is a powerhouse of energy for the coming season. If you are planting several varieties, dahlia collections can provide a convenient way to plan a colorful display.
Inspecting the Tuber
A healthy tuber should feel firm, not mushy or shriveled. It is normal for them to have some loose skin or even a bit of surface mold, which you can simply brush off. The most important parts are the "neck" and the "eye." The neck is the narrow part that connects the tuber to the old stem. The eye is a small bump or sprout located on the "head" of the tuber, near where it meets the stem. This is where the new growth will emerge.
Handling with Care
While tubers are sturdy, the necks can be somewhat fragile. If a neck snaps, that specific tuber may not be able to send energy to the sprout. Handle them gently as you move them to the garden. If you see a sprout already starting, don't worry. This is a sign the plant is ready to grow. Just be careful not to knock the sprout off during the planting process.
Step-by-Step Planting Guide
Once your soil is warm and your spot is picked, it is time to get the tubers into the ground. Following these steps ensures they are at the right depth and orientation for success.
1. Dig the Hole
Dig a hole that is about four to six inches deep. If you are planting several pom pom dahlias in a row, you can dig a long trench instead of individual holes. This depth protects the tuber from temperature swings and provides a sturdy base for the tall stems that will follow.
2. Place the Tuber Horizontally
Lay the tuber flat in the bottom of the hole. Some gardeners try to plant them vertically, but laying them horizontally is actually better for the plant. Make sure the "eye" or the sprout is facing upward or toward the center of the hole. This gives the sprout the shortest and easiest path to the surface.
3. Add Support Early
If you are growing a variety that reaches over three feet, it is helpful to place a stake in the ground now. By putting the stake in at planting time, you avoid accidentally poking a hole through the tuber later in the season. A simple bamboo cane or a wooden garden stake works perfectly. Place it about two inches away from the tuber.
4. Fill with Soil
Gently cover the tuber with soil. Do not pack the soil down too hard; you want it to be firm enough to hold the tuber in place but loose enough for the tender sprout to push through. Do not add water immediately unless the soil is bone-dry. The tuber has enough stored moisture to get started on its own.
Caring for New Growth
For the first few weeks, your dahlia will be busy growing roots underground. You might not see anything happening on the surface, but don't worry—there is a lot of work going on beneath the soil. Longfield's dahlia planting guide also covers depth, spacing, support, and early watering.
The First Sprouts
You will usually see green shoots breaking through the soil within two to three weeks, depending on the weather. Once the plants are about three or four inches tall, you can start watering them. This is the stage where the plant transitions from using the energy stored in the tuber to using the nutrients and water it finds in the soil.
Watering Correctly
Dahlias prefer a "deep, then dry" approach. Instead of giving them a little bit of water every day, give them a thorough soaking two or three times a week. This encourages the roots to grow deep into the ground, making the plant more resilient during the hottest parts of the summer. Always try to water at the base of the plant to keep the leaves dry, which helps prevent common leaf issues.
Feeding Your Plants
As your pom pom dahlias grow, they will appreciate a little extra nutrition. Use a fertilizer that is designed for flowers. These typically have a lower first number (nitrogen) and higher middle and last numbers (phosphorus and potassium). High nitrogen can cause the plant to grow lots of green leaves but very few flowers. Applying a balanced liquid or granular fertilizer once a month starting in mid-summer will help keep the blooms coming.
The Secret to More Flowers: Pinching
If you want your pom pom dahlia to be a flower-producing machine, you should "pinch" it. This might feel a bit scary the first time you do it, but it is one of the best things you can do for your plant. Learn more about pinching dahlias for more blooms.
Why We Pinch
When a dahlia grows, it naturally wants to send up one main center stalk. If left alone, this stalk will grow very tall and produce one flower at the top. By pinching off the top of that main stem, you signal the plant to branch out from the sides. This creates a bushier plant with many more stems, which means many more pom pom blooms.
How to Pinch
Wait until your plant is about 12 inches tall and has four sets of leaves. Use your fingers or a pair of clean garden snips to remove the very top of the center stem, just above the top set of leaves. Within a week, you will see two new stems growing where there was only one. This simple step can double or triple your flower count for the season.
What to do next:
- Watch for your plant to hit 12 inches in height.
- Locate the central growing tip.
- Snip off the top 2 inches of the main stem.
- Observe as side branches begin to form over the next few days.
Supporting Your Pom Pom Dahlias
While pom pom flowers are small, a fully grown plant can become top-heavy when it is covered in dozens of blooms. Providing support prevents the stems from snapping during a summer thunderstorm.
Single Staking
The easiest method is to tie the main stem to the stake you placed at planting time. Use a soft material like twine or garden ribbon. Avoid wire, which can cut into the green stems. As the plant grows taller, add another tie every 12 inches.
The Corral Method
If you are growing a whole row of pom poms, you can use the corral method. Drive a sturdy stake into the four corners of your dahlia bed. Wrap twine around the stakes at a height of about 18 inches, then again at 36 inches. This creates a "cage" that the plants can grow into, using each other for support. This is a very efficient way to keep a large group of plants upright and looking tidy.
Planting Pom Pom Dahlias in Containers
If you don't have a large garden space, you can still enjoy these beautiful flowers. Pom pom varieties are actually some of the best dahlias for pots because their blooms are in proportion to the container. Browse container-friendly dahlia collections when planning a potted display.
Choose the Right Pot
A single dahlia tuber needs a pot that holds at least 5 to 7 gallons of soil. Look for a container that is about 12 to 15 inches in diameter and just as deep. Most importantly, ensure the pot has large drainage holes in the bottom.
Use Quality Potting Mix
Do not use garden soil in your pots. It is too heavy and will pack down, preventing the roots from getting the air they need. Use a high-quality potting mix that contains peat moss or coconut coir and perlite. This ensures the soil stays light and drains quickly.
Container Aftercare
Plants in pots dry out much faster than those in the ground. During the height of summer, you may need to water your container dahlias every day. Because you are watering frequently, nutrients will wash out of the soil, so be sure to use a liquid flower fertilizer every two weeks to keep the plant healthy and blooming.
Harvesting Your Blooms
One of the best reasons to plant pom pom dahlias is to have a constant supply of cut flowers for your home. The more you cut them, the more the plant will bloom. Longfield's guide to cutting and arranging dahlias offers additional harvesting advice.
When to Cut
Unlike some flowers that continue to open after they are cut, dahlias should be harvested when they are nearly fully open. Look for blooms where the petals are fully unfurled but the back of the flower still looks fresh and firm. If the petals on the back are starting to feel papery or turn brown, the flower is past its prime.
Cutting Technique
Use a sharp, clean pair of scissors or garden snips. Cut the stem as long as possible, even if it means cutting into a bit of the leafy growth. This encourages the plant to send up a new, long stem from the base. Place the stems immediately into a bucket of room-temperature water.
Vase Life
Pom pom dahlias have a great vase life, often lasting five to seven days. To keep them looking their best, change the water in the vase every day and trim a tiny bit off the bottom of the stems. Keeping them out of direct sunlight and away from ripening fruit will also help them stay fresh longer.
Preparing for the End of the Season
In most parts of the United States, dahlias are treated as annuals or "tender perennials." This means they will grow all summer but will not survive a freezing winter in the ground.
After the First Frost
When the first hard frost hits, the green foliage of your dahlias will turn black or brown. This is normal. At this point, you have two choices. You can simply leave them in the ground and plant new tubers from us next spring, or you can "lift" the tubers to store them for the winter.
Lifting and Storing
If you choose to save your tubers, wait about a week after the frost has killed the tops. This allows the tubers to "cure" in the ground. Cut the stems down to about four inches, then use a garden fork to gently lift the cluster of tubers out of the soil. Brush off the dirt and let them dry in a shady, frost-free spot for a day or two.
Store the tubers in a box filled with slightly damp peat moss, vermiculite, or wood shavings. Keep the box in a cool, dark place (between 40°F and 50°F) where they won't freeze. In the spring, you can take them out, check for new eyes, and start the planting process all over again. See Longfield's complete guide to overwintering dahlias for more details.
Conclusion
Planting pom pom dahlias is a wonderful way to bring color, symmetry, and joy to your summer landscape. By choosing a sunny spot with good drainage and waiting for the soil to warm up, you set the stage for a spectacular display. These little geometric spheres are not just flowers; they are a testament to the rewards of simple, consistent care.
At Longfield Gardens, we take pride in providing high-quality tubers that are ready to thrive in your garden. Whether you are planting your very first tuber or adding to a lifelong collection, the process is straightforward and the results are consistently beautiful. We invite you to explore the different colors and varieties available to create a garden that feels uniquely yours. For gardeners planting several tubers, spring bulk buys can help fill a border or cutting garden.
Final Tips for Success:
- Select a site with at least 8 hours of sun.
- Plant tubers 4–6 inches deep once the soil hits 60°F.
- Pinch the center stem at 12 inches to maximize blooms.
- Water deeply and consistently throughout the summer heat.
We look forward to helping you grow a more beautiful world, one pom pom dahlia at a time.
FAQ
How far apart should I plant pom pom dahlias?
Space your pom pom dahlias 12 to 18 inches apart. While the flowers are small, the plants grow quite bushy and need plenty of room for air to circulate between the leaves. Proper spacing helps keep the plants healthy and makes it easier for you to reach in and harvest the blooms.
When will my pom pom dahlias start blooming?
Most dahlias begin to bloom about 8 to 12 weeks after planting. For pom pom varieties, you can usually expect to see your first flowers in mid to late July, with the peak of production happening in August and September. They will continue to produce flowers until the first hard frost of the autumn.
Can I grow pom pom dahlias in large pots?
Yes, pom pom dahlias are excellent candidates for container gardening. Ensure you use a pot that holds at least 5 gallons of soil and has excellent drainage. Because they are in a confined space, container dahlias will need more frequent watering and regular fertilizing compared to those planted in the ground.
Do pom pom dahlias need full sun?
For the best results, pom pom dahlias need at least six to eight hours of direct sunlight every day. Sunlight provides the energy they need to produce their intricate, round flowers and keep their stems strong. In very hot climates, they can benefit from some light shade in the late afternoon, but morning sun is vital.
