Table of Contents
- Introduction
- What Makes a Pom Pom Dahlia Unique?
- Choosing the Best Spot for Your Dahlias
- When to Put Your Dahlias in the Ground
- Preparing the Soil for Planting
- Step-by-Step: How to Plant Pom Pom Dahlias
- The Most Important Rule: Do Not Water Yet
- Early Growth and "Pinching"
- Supporting and Staking Your Pom Poms
- Feeding Your Dahlias for Maximum Blooms
- The Importance of Deadheading
- Common Pom Pom Dahlia Varieties to Consider
- Dealing with Garden Visitors
- What to Do at the End of the Season
- Growing Pom Pom Dahlias in Containers
- Conclusion
- FAQ
Introduction
There is something deeply satisfying about the perfect symmetry of a pom pom dahlia. These charming blooms, with their tightly quilled petals and neat, globe-like shapes, look as though they were crafted by hand. Whether you are looking to add texture to your flower beds or want to grow the perfect focal point for a summer bouquet, pom pom dahlias are a delightful choice. At Longfield Gardens, we love these dahlias for their prolific blooming habits and their ability to stay upright more easily than some of the larger, heavier-headed types.
If you have never grown these pom pom dahlias before, you are in for a treat. They are easy to care for, come in a stunning array of colors, and provide a nearly endless supply of blooms from midsummer all the way to the first frost. This guide will walk you through everything you need to know to get your pom pom dahlias into the ground and off to a strong start. We will cover site selection, planting depth, and the simple care steps that ensure your garden is filled with these geometric wonders.
Growing pom pom dahlias is a rewarding experience that brings a touch of whimsy and elegance to any outdoor space. By following a few basic principles, you can enjoy a season full of vibrant, perfectly round blossoms.
What Makes a Pom Pom Dahlia Unique?
Before we dig into the planting process, it is helpful to understand what sets pom pom dahlias apart from other types, like decorative or dinnerplate varieties. In the world of dahlias, "pom pom" is a specific classification. These flowers are known for being perfectly spherical and relatively small, usually measuring two inches or less in diameter.
Their petals are "involute," which is a fancy way of saying they roll inward to form tiny tubes. This structure gives the flower its signature honeycomb appearance. Because the blooms are smaller and the stems are typically quite sturdy, pom pom dahlias are often more resilient in the wind and rain than their giant cousins. They are workhorses in the garden, producing dozens of flowers on a single plant throughout the season.
Choosing the Best Spot for Your Dahlias
Success with pom pom dahlias starts with picking the right location. Like all dahlias, these plants are sun-lovers. To get the most blooms and the strongest stems, you need to match the plant’s needs to the spot you have available. For a broader overview, see All About Dahlias.
Sunlight Requirements
Your pom pom dahlias should receive at least six to eight hours of direct sunlight every day. Sunlight is the "fuel" that allows the plant to produce those intricate flowers. If they are planted in too much shade, the stems will become "leggy" or stretched out as they reach for the light, and you will see far fewer blooms.
In very hot climates (such as the Southern US), dahlias appreciate a little bit of shade in the late afternoon when the sun is at its most intense. However, for most gardeners, the sunnier the spot, the better.
Soil and Drainage
"Drainage" simply refers to how quickly water moves through the soil. Dahlias have tuberous roots that can be sensitive to sitting in soggy ground. If the soil stays too wet for too long, the tubers can rot before they even have a chance to sprout.
We recommend planting in loose, loamy soil that is rich in organic matter. If you have heavy clay soil that stays wet after a rain, you can improve the spot by mixing in some compost or aged manure. This helps create air pockets in the soil and allows water to move away from the tubers more effectively.
Key Takeaway: Choose a sunny spot with soil that doesn't stay soggy. If water puddles in an area for hours after a rain, it is likely too wet for dahlias.
When to Put Your Dahlias in the Ground
Timing is perhaps the most important factor when learning how to plant pom pom dahlias. Because these are tropical plants originally from Mexico and Central America, they have no tolerance for frost or cold soil.
The 60-Degree Rule
Wait to plant your dahlia tubers until the danger of frost has completely passed and the soil has warmed up. A good rule of thumb is to plant your dahlias around the same time you would plant your tomatoes. Ideally, the soil temperature should be around 60°F.
If you plant too early into cold, wet soil, the tuber will just sit there and may eventually decay. It is much better to wait an extra week or two for the weather to stabilize. The plants will quickly make up for the lost time once the sun starts warming the earth.
A Note on USDA Zones
Dahlias are considered "tender perennials." This means they can stay in the ground year-round in warm climates (usually USDA zones 8–11). If you live in a colder region (zones 3–7), you will plant them in the spring, enjoy them all summer, and then either treat them as annuals or dig them up to store indoors over the winter. At Longfield Gardens, we time our shipments based on your specific hardiness zone, so your tubers arrive when the weather is just about right for planting. If you need help finding your zone, check the Hardiness Zone Map.
Preparing the Soil for Planting
You don't need a degree in soil science to grow beautiful dahlias, but a little bit of preparation goes a long way. Before you start digging, clear the area of any weeds or large rocks.
If your soil is a bit lean, you can spread a two-inch layer of compost over the planting area and gently work it into the top few inches of soil. Avoid using high-nitrogen fertilizers at this stage. While nitrogen helps plants grow lots of green leaves, too much of it early on can actually discourage the plant from producing flowers later.
Dahlias prefer a slightly acidic to neutral soil pH (around 6.0 to 7.0). Most garden soils fall into this range naturally, but if you've struggled with plants in the past, a simple soil test from a local extension office can provide specific guidance for your yard.
Step-by-Step: How to Plant Pom Pom Dahlias
Once the soil is warm and your spot is ready, it is time to plant. For a fuller walkthrough, see How to Plant Dahlias. Planting a dahlia tuber is very similar to planting a potato.
1. Dig the Hole
Dig a hole that is about 4 to 6 inches deep. If you are planting multiple pom pom dahlias, space the holes about 12 to 18 inches apart. While some larger dahlias need 3 feet of space, pom poms are often slightly more compact and can be spaced a bit closer to create a lush, full look.
2. Place the Tuber
Look at your dahlia tuber. You should see a "neck" that connects the tuberous roots to a piece of the previous year's stem. This is where the "eyes" are located. The eyes are the small bumps or sprouts that will become the new stems.
Lay the tuber horizontally in the bottom of the hole with the eyes facing up. If you can't tell which side is the top, don't worry—the plant is smart enough to find its way toward the sun regardless of how it is positioned.
3. Add Support (Optional but Recommended)
Even though pom pom dahlias have sturdier stems than many other types, they can still benefit from a bit of support as they grow. It is much easier to put a stake in the ground now than it is to try to do it later when the plant is large and you risk poking a hole through the tuber.
Drive a wooden or metal stake into the ground a few inches away from the tuber. As the plant grows, you can gently tie the stems to the stake for extra stability during summer storms.
4. Cover with Soil
Fill the hole back in with soil. You don't need to pack it down hard; just a gentle pat to ensure there aren't large air pockets around the tuber is enough.
What to Do Next:
- Check your local frost dates to ensure it’s safe to plant.
- Dig holes 4-6 inches deep and 12-18 inches apart.
- Place tubers horizontally with the "eye" facing up.
- Drive a stake into the ground now to save effort later.
The Most Important Rule: Do Not Water Yet
This is the one area where many well-meaning gardeners make a mistake. When we plant most things, our instinct is to give them a deep drink of water immediately. With dahlias, you should resist this urge.
Because the tuber doesn't have a root system yet, it cannot take up water. If the soil is already slightly moist from spring rains, that is all the moisture the tuber needs to "wake up." Adding extra water at this stage can lead to rot.
Wait until you see the first green shoots poking through the surface of the soil. Once the plant has leaves, it has a way to process water, and you can begin a regular watering schedule. If your climate is extremely dry and the soil is bone-dry at planting time, a very light sprinkling is okay, but generally, less is more during the first few weeks.
Early Growth and "Pinching"
As your pom pom dahlias begin to grow, they will usually send up one main center stalk. While it is tempting to just let it grow, there is a simple trick to get a much bushier plant with significantly more flowers: pinching. For more care tips, see 8 Tips for Growing Better Dahlias.
How to Pinch Your Dahlias
When your plant is about 12 to 16 inches tall and has four sets of leaves, use your fingers or a clean pair of snips to remove the very top of the center stem. It feels a bit wrong to "injure" your healthy plant, but this actually sends a signal to the dahlia to stop putting all its energy into one tall stalk and start branching out from the sides.
Pinching results in a sturdier, more compact plant that doesn't get top-heavy. Most importantly for pom pom lovers, more branches mean more of those beautiful round blooms.
Watering Established Plants
Once your dahlias are a few inches tall and growing vigorously, they will become quite thirsty. In the heat of the summer, they generally need about an inch of water per week.
When you water, aim for the base of the plant rather than spraying the leaves. Keeping the foliage dry helps prevent common issues like powdery mildew. Deep, infrequent watering is always better than a light daily sprinkle. You want the water to reach deep into the soil to encourage the roots to grow downward.
Supporting and Staking Your Pom Poms
As mentioned earlier, pom pom dahlias are generally more self-supporting than the massive 10-inch "dinnerplate" varieties. However, a fully grown dahlia can still reach 3 or 4 feet in height. When the plant is loaded with dozens of blooms and a heavy summer rain hits, the weight can cause the stems to lean or snap.
If you placed a stake at planting time, simply use some soft garden twine or even strips of old t-shirts to loosely tie the main stems to the stake every 12 inches or so as the plant grows. You want to give the plant some support without strangling the stems.
Another popular method for those planting in rows is "corralling." You can place stakes at the corners of your dahlia bed and run twine around the perimeter to keep the plants from flopping into the walkways.
Feeding Your Dahlias for Maximum Blooms
Dahlias are "heavy feeders," which means they use a lot of nutrients to produce their spectacular show. However, the type of food you give them matters just as much as the amount.
For the best results, use a fertilizer that is lower in nitrogen and higher in phosphorus and potassium (look for a ratio like 5-10-10 on the label).
- Nitrogen (the first number) promotes green, leafy growth.
- Phosphorus (the middle number) promotes root development and flower production.
- Potassium (the last number) supports overall plant health and tuber quality.
Start fertilizing about a month after planting and continue every 3 to 4 weeks until early autumn. Always follow the instructions on the fertilizer package, as more is not always better. Over-fertilizing can lead to weak stems and fewer flowers.
The Importance of Deadheading
If you want your pom pom dahlias to keep blooming until the first frost, you must "deadhead." Deadheading is simply the process of removing faded or spent flowers. For a broader refresher, see How and Why to Deadhead Flowers.
When a dahlia flower begins to wither, the plant starts putting its energy into creating seeds. If you remove the old flower before it can make seeds, the plant says, "I'm not done yet!" and produces more buds.
To deadhead correctly, don't just pull off the flower head. Follow the stem down to where it meets a main branch or a set of leaves and make your cut there. This keeps the plant looking tidy and encourages new growth from the leaf axils.
Key Takeaway: The more you cut your dahlias, the more they will bloom. Don't be afraid to harvest plenty of flowers for indoor arrangements!
Common Pom Pom Dahlia Varieties to Consider
When you browse the selection at Longfield Gardens, you will find several classic pom pom and ball-style dahlias that are perfect for beginners and experts alike. Here are a few favorites that consistently perform well:
- Franz Kafka: A stunning lavender-pink pom pom with incredibly uniform petals. It is a prolific bloomer and looks beautiful in bouquets.
- Natal: A deep, velvety red that adds drama to the garden. Its dark color makes the honeycomb structure of the petals really pop.
- Stolze von Berlin: A soft, lilac-pink variety that has been a garden favorite for decades. It is reliable and very dainty.
- Little Robert: A fun bicolor variety that usually features pinkish-purple petals with darker tips.
Each of these varieties stays true to the pom pom form, providing those small, 2-inch globes that define the category.
Dealing with Garden Visitors
Dahlias are generally robust, but they do have a few common fans in the insect world. For a closer look at likely problems, see Common Dahlia Pests and Diseases.
Slugs and Snails
Slugs love the tender, juicy shoots of young dahlias. When your plants are first emerging from the soil, keep a close eye out for silvery trails or holes in the leaves. You can protect your plants by using a pet-safe slug bait or simply hand-picking them in the early evening. Once the plants are about a foot tall and the stems become tougher, slugs are usually much less of a problem.
Earwigs and Thrips
Sometimes you might notice small holes in the flower petals. This is often the work of earwigs or thrips. While they rarely kill the plant, they can make the blooms look a bit untidy. Encouraging natural predators like ladybugs and birds into your garden is a great long-term strategy for keeping these pests in check.
What to Do at the End of the Season
When the first frost arrives, your dahlia foliage will turn black almost overnight. Don't worry—this is normal! The tubers underground are still perfectly fine.
If you live in a warm climate (Zone 8 or higher), you can simply cut the stems back to a few inches above the ground and cover the area with a thick layer of mulch to protect them for the winter.
If you live in a colder climate, you have a choice:
- Treat them as annuals: Many gardeners simply let the tubers go and buy fresh ones from us the following spring. This is the easiest, stress-free option.
- Dig and store: If you have a variety you absolutely love, you can dig up the tubers. Cut the stems back, gently lift the tuber clump with a garden fork, wash off the soil, and let them dry in a frost-free place for a few days. Then, store them in a box with slightly damp peat moss or vermiculite in a cool, dark place (like a basement) that stays between 40°F and 50°F. For step-by-step storage help, see How to Overwinter Dahlia Tubers.
Growing Pom Pom Dahlias in Containers
If you don't have a large garden plot, you can still enjoy pom pom dahlias! They do very well in containers. For more ideas, see Can Dahlias Grow in Containers?.
Choose a pot that is at least 12 inches deep and 12 inches wide with good drainage holes in the bottom. Use a high-quality potting mix (not garden soil) and follow the same planting depth and "no water until sprouts" rules.
Container-grown dahlias will dry out faster than those in the ground, so you may need to water them more frequently during the peak of summer. They also appreciate a regular liquid fertilizer every two weeks since nutrients leach out of pots more quickly.
Conclusion
Planting pom pom dahlias is one of the most rewarding ways to spend a spring afternoon. These plants ask for very little—just sun, warmth, and a bit of patience—and in return, they provide a spectacular display of geometric beauty that lasts for months. Whether you are growing them for competition, for cutting, or simply to enjoy the view from your porch, pom poms are sure to become a highlight of your garden.
At Longfield Gardens, we take pride in providing high-quality tubers that are ready to thrive in your yard. Remember that gardening is an adventure, and each season brings new lessons and beautiful surprises.
- Wait for the warmth: Don't rush your tubers into cold soil.
- Pinch for success: Snip the tops when they are a foot tall for a bushier plant.
- Water wisely: Only start watering once you see green growth.
- Enjoy the harvest: The more you cut, the more they bloom!
Growing pom pom dahlias is about more than just the flowers; it's about the joy of watching a small, humble tuber transform into a masterpiece of natural engineering.
We invite you to explore the different colors and varieties available and start planning your most beautiful summer garden yet. If you ever have questions about your plants, our team is always here to help you succeed. Happy planting!
FAQ
Do pom pom dahlias need more support than other types?
Actually, pom pom dahlias often need less support than dinnerplate varieties because their flowers are much smaller and lighter. However, the plants can still reach 3 to 4 feet tall, so a simple stake or a small tomato cage is a great way to prevent the stems from leaning or snapping during heavy summer winds.
Can I grow pom pom dahlias from seed?
While you can grow dahlias from seed, they will not be "true to type." This means if you plant a seed from a pom pom dahlia, the resulting flower might be a different shape or color altogether. To ensure you get the exact pom pom shape and color you want, it is best to plant tubers, which are clones of the parent plant.
Why are my pom pom dahlias not blooming?
The most common reasons for a lack of blooms are too much shade or too much nitrogen in the fertilizer. Ensure your plants get at least 6 to 8 hours of sun and switch to a fertilizer with a higher middle number (phosphorus). Also, make sure you are deadheading old flowers regularly to encourage the plant to produce new buds.
How deep should I plant pom pom dahlia tubers?
You should plant dahlia tubers about 4 to 6 inches deep. Place the tuber horizontally in the hole with the "eye" or the small sprout facing upward. Cover it with soil and avoid watering until you see the first green shoots emerge from the ground, which usually takes two to three weeks depending on the temperature.