How Geoff and Heather Grow Dahlias

Table of Contents

1. Introduction
2. Choosing the Right Varieties
3. Preparing the Soil for Success
4. The Geoff and Heather Staking Method
5. Planting with Precision
6. The Importance of Pinching
7. The Art of Disbudding for Giant Blooms
8. Feeding and Watering Routine
9. Maintaining Health Through the Season
10. Late Season Care and Deadheading
11. Lifting and Storing Tubers
12. Conclusion
13. FAQ

Introduction

Walking through a garden filled with dinnerplate dahlias is an experience that stays with you. The massive, vibrant blooms and the architectural height of the plants create a sense of wonder that few other flowers can match. Many gardeners find inspiration in the world-class displays created by expert growers like Geoff and Heather, whose garden has become a benchmark for dahlia excellence. Their success isn't due to magic but rather a commitment to a few clear, effective growing techniques that anyone can master.

At Longfield Gardens, we believe that every home gardener has the potential to grow spectacular flowers, and our dahlia collections are a great place to begin. By understanding the specific habits and needs of dahlias, you can transform your backyard into a colorful sanctuary. This guide focuses on the methods used by top-tier growers to produce the largest, healthiest blooms possible. We will walk you through the entire process, from preparing the soil to the specialized art of disbudding.

The journey to a prize-worthy dahlia garden begins with patience and a focus on the basics. Whether you are a beginner or a seasoned gardener, the steps outlined here will help you achieve consistent results. By the end of this article, you will have a clear roadmap for growing dahlias that are as healthy as they are beautiful.

Choosing the Right Varieties

Success starts with the tubers you select. Expert growers often focus on specific categories of dahlias that provide the most visual impact. If you want to replicate a high-end garden look, you should look for varieties known for their size and form. Dinnerplate dahlias are a favorite because their blooms can reach up to 10 inches in diameter. Decorative dahlias are another excellent choice, offering perfectly symmetrical petals that look stunning in both the garden and in vases.

We recommend starting with varieties that are known for their sturdy stems and reliable bloom cycles. At Longfield Gardens, we offer a wide range of these high-performance tubers. When selecting your plants, consider a mix of colors and shapes. Cactus dahlias add a unique texture with their spiky petals, while ball dahlias provide a compact, tidy appearance that balances out the larger varieties.

Think about the height of the plants as well. Most exhibition-style dahlias grow to be four or five feet tall. You will need to plan your garden layout so these tall beauties don't shade out smaller perennials. Placing them at the back of a border or in a dedicated "cutting garden" area often yields the best results.

Key Takeaway: Choose a mix of dinnerplate and decorative varieties to achieve a high-impact, professional-looking garden. Selecting quality tubers is the first step toward healthy, vibrant plants.

Preparing the Soil for Success

High-performing dahlias are "heavy feeders," meaning they require a lot of nutrients to produce those massive flowers. Expert growers spend a significant amount of time preparing their soil before the first tuber even touches the ground. The goal is to create a growing medium that is rich in organic matter and offers excellent drainage. For more on site selection, see Where Do Dahlias Grow? Tips for the Perfect Garden Spot.

Dahlias do not like "wet feet." If the soil stays soggy, the tubers can rot before they have a chance to sprout. To improve drainage, you can mix in compost or well-rotted manure. This not only helps water move through the soil but also provides a steady supply of nutrients as the plants grow. If you have heavy clay soil, consider planting in raised beds where you have more control over the soil composition.

The ideal soil pH for dahlias is slightly acidic to neutral, roughly between 6.0 and 7.0. You can easily test your soil with a simple kit from a local garden center. If your soil is too acidic, a bit of lime can help; if it is too alkaline, sulfur can bring the levels down. Most importantly, make sure the spot you choose gets at least six to eight hours of direct sunlight every day. Sunlight is the fuel that dahlias use to create their spectacular blooms.

What to Do Next: Soil Preparation

• Test your soil pH to ensure it is in the 6.0–7.0 range.
• Incorporate 2–3 inches of compost into your planting area.
• Identify the sunniest spot in your yard with the best drainage.
• Clear away any weeds or grass that might compete for nutrients.

The Geoff and Heather Staking Method

One of the most noticeable differences between a casual garden and an expert one is the support system. For more practical support tips, see How to Pinch and Stake Dahlias. Dahlias have hollow, somewhat brittle stems that can easily snap under the weight of a large flower or during a summer thunderstorm. Expert growers like Geoff and Heather use a method of individual staking that provides maximum security for every plant.

Instead of waiting for the plant to grow tall, you should put your stakes in the ground at the time of planting. This prevents you from accidentally driving a stake through the tuber later in the season. Use sturdy stakes made of wood, bamboo, or coated metal, at least five to six feet tall. Drive them about 12 inches into the ground so they are stable.

As the plant grows, you will tie the main stem to the stake every 12 to 18 inches. Use soft twine or garden tape that won't cut into the fleshy stems. The goal is to support the plant without strangling it. This individual attention ensures that each dahlia has the space it needs to breathe and grow, reducing the risk of fungal issues and ensuring the blooms are displayed prominently.

Key Takeaway: Always install your stakes at the time of planting to protect the tubers. Individual staking provides the strongest support for heavy dinnerplate varieties.

Planting with Precision

Once your soil is ready and your stakes are in place, it is time to plant. For a broader planting overview, see All About Dahlias. In most regions, this happens in late spring when the danger of frost has passed and the soil has warmed to about 60°F. Planting too early in cold, wet soil can lead to slow growth or rot. If you live in a cooler climate, you can start your tubers indoors in pots about four weeks before the last frost to give them a head start.

Dig a hole about 4 to 6 inches deep next to your stake. Lay the tuber horizontally with the "eye" or the sprout pointing upward. If you aren't sure where the eye is, don't worry—the plant will find its way to the surface. Cover the tuber with soil, but do not water it immediately unless the soil is exceptionally dry. The tuber has enough stored energy and moisture to get started, and overwatering at this stage is a common mistake.

Space your plants about 18 to 24 inches apart. While they look small now, they will quickly fill out into large, bushy shrubs. Proper spacing is essential for air circulation. When air can move freely between the plants, the leaves dry faster after rain, which helps keep the garden healthy and vibrant throughout the season.

The Importance of Pinching

If you want a dahlia plant that is full of flowers rather than one single tall stalk, you must "pinch" your plants. For a fuller walkthrough, see How to Pinch and Stake Dahlias. This is a technique used by all professional growers to encourage branching. When your dahlia is about 12 to 16 inches tall and has four sets of leaves, snip off the very top of the center stem.

This might feel counterintuitive, but it is one of the best things you can do for your garden. By removing the dominant center terminal, you signal the plant to send its energy to the side buds. Within a week or two, you will see new stems growing from the leaf axils. This results in a bushier plant with a much stronger structure and, ultimately, many more flowers.

A pinched plant is also easier to manage and support. Instead of one heavy top-heavy stem, you have a balanced plant with multiple flowering points. This simple step, performed early in the season, makes a massive difference in the overall volume of color you will see in August and September.

What to Do Next: Early Season Care

• Wait for the plant to reach 12 inches in height.
• Identify the central growing tip.
• Use clean garden snips to remove the top 1–2 inches of the stem.
• Monitor for new side growth over the following two weeks.

The Art of Disbudding for Giant Blooms

If you have ever wondered how growers get those massive, competition-sized blooms, the secret is "disbudding." For more bloom-boosting techniques, see How Dahlias Grow. This is the process of removing excess flower buds to allow the plant to focus all its energy on a single, perfect flower. While it requires a bit of extra effort, the results are truly spectacular.

On a typical dahlia stem, you will see a cluster of three buds at the end of a branch. There is one central bud (the terminal bud) and two smaller side buds. To get a giant bloom, you carefully pinch off the two side buds, leaving only the central one. You can also remove the next one or two sets of side buds further down the stem.

This technique ensures that the resulting flower gets the maximum amount of nutrients and water. It also results in a longer stem for cutting, as the plant isn't busy producing multiple small flowers in a cramped space. If you prefer a "garden look" with hundreds of smaller blooms, you can skip this step. However, for that iconic "Geoff and Heather" look, disbudding is essential for at least a few of your favorite plants.

Key Takeaway: Disbudding redirects the plant's energy into a single bloom, resulting in larger flowers and longer stems. It is the hallmark technique of expert dahlia growers.

Feeding and Watering Routine

Dahlias are thirsty and hungry plants, especially during the heat of mid-summer. However, their needs change as they progress through the season. Early on, they benefit from a balanced fertilizer to help build strong roots and green foliage. Once they start forming buds, they need a fertilizer that is higher in phosphorus and potassium.

In the gardening world, many experts use a water-soluble fertilizer every two weeks. This "liquid feed" approach ensures the nutrients are immediately available to the roots. Look for a fertilizer with a ratio similar to 5-10-10 or 10-20-20. This encourages flower production rather than just more green leaves.

Watering should be deep and consistent. Instead of a light sprinkle every day, give your dahlias a thorough soaking two or three times a week. Aim the water at the base of the plant to keep the foliage dry. This encourages the roots to grow deeper into the soil, making the plant more resilient during dry spells. If the weather is particularly hot, you may need to increase the frequency, but always check the soil moisture first—it should feel like a wrung-out sponge, not a puddle.

Maintaining Health Through the Season

A healthy garden is a happy garden. While dahlias are generally robust, they can occasionally attract unwanted visitors like slugs, snails, or earwigs. The best approach is a proactive one. Keeping the area around the base of your plants free of debris and fallen leaves removes the hiding spots for these pests.

For slugs and snails, many gardeners find success with simple organic baits or by creating a dry barrier around the stems. If you notice small holes in the leaves, a quick evening inspection with a flashlight can help you identify the culprit. Most issues can be handled easily if you catch them early.

Fungal issues like powdery mildew can sometimes appear in late summer when the air is humid. The best defense is the spacing and airflow we mentioned earlier. If you do see a white, dusty coating on the leaves, you can use a gentle neem oil spray or a mixture of baking soda and water to help manage it. Always follow the instructions on any product label and apply treatments during the cool of the evening to avoid leaf burn.

Late Season Care and Deadheading

As the season progresses into late August and September, your dahlias will be at their peak. This is the most rewarding time in the garden, but it still requires a little maintenance. Deadheading—the process of removing spent blooms—is vital for keeping the plant productive. If you leave old flowers on the plant, it will start to produce seeds, which signals the plant to stop flowering.

When you remove a dead flower, don't just snip off the head. Cut the stem back to the next set of leaves or the next side bud. This keeps the plant looking tidy and encourages new growth. You will find that the more you cut your dahlias for indoor bouquets, the more they will bloom.

In the late season, you may also need to add extra support. As the plants reach their full height and the blooms become more numerous, check your ties and stakes. Adding a few extra loops of twine can prevent a sudden autumn wind from damaging your hard work. Enjoy the spectacle; this is what all those months of preparation were for.

What to Do Next: Late Season Maintenance

• Check the garden daily for spent blooms.
• Cut flowers for bouquets to encourage more budding.
• Inspect ties and stakes to ensure they are holding firm.
• Continue your feeding schedule until the first frost is imminent.

Lifting and Storing Tubers

In many parts of the United States, dahlias are not hardy enough to stay in the ground over winter. Once the first hard frost blackens the foliage, it is time to "lift" the tubers and store them for next year. This is one of the best parts of growing dahlias—your collection can grow year after year as the tubers multiply. For step-by-step winter care, see How to Overwinter Dahlias.

After the frost, cut the stems down to about 4 inches. Let the tubers sit in the ground for a few days to "cure" and then carefully dig them up using a garden fork. Be gentle to avoid neck damage to the tubers. Wash off the excess soil and let them dry in a frost-free, shaded area for a day or two.

Store your tubers in a cool, dark, and dry place. Most gardeners use boxes filled with slightly damp peat moss, vermiculite, or wood shavings. The temperature should ideally stay between 40°F and 50°F. Check on them once or twice during the winter to make sure they aren't drying out too much or showing signs of rot. If they look shriveled, a light misting of water can help.

Key Takeaway: Lifting and storing tubers allows you to enjoy your favorite varieties for years to come. Proper winter storage is the key to a successful start the following spring.

Conclusion

Growing dahlias like a pro is a journey that rewards you with some of the most spectacular colors and forms in the botanical world. By focusing on quality tubers, proper staking, and the art of disbudding, you can create a display that rivals the most famous gardens. Remember that gardening is a continuous learning process, and each season brings new opportunities to refine your skills and enjoy the beauty of nature.

We are here to support you every step of the way. At Longfield Gardens, our mission is to help you create a more beautiful yard with premium plants and practical advice. We stand behind our quality with a 100% Quality Guarantee, ensuring that your items arrive in prime condition and are true to variety. If you ever have questions about your plants' performance during their first growing season, our team is ready to help.

• Start with high-quality tubers and rich, well-drained soil.
• Stake early and pinch your plants to create a sturdy, bushy structure.
• Use disbudding to achieve those iconic, giant dinnerplate blooms.
• Water deeply and feed regularly with a high-potassium fertilizer.

"The secret to a world-class dahlia garden is simply a series of small, thoughtful actions taken at the right time. With a bit of patience and the right techniques, your garden can become a neighborhood landmark."

We invite you to explore our selection and start planning your most beautiful dahlia season yet. For more on tuber basics, read Dahlia Tubers: What You Need to Know. Happy gardening!

FAQ

How do I get my dahlia flowers to be as large as possible?

The key to massive blooms is a combination of variety selection and a technique called disbudding. Start with dinnerplate varieties, and then remove the two side buds from each flowering cluster, leaving only the central terminal bud. This forces the plant to send all its energy into one single, giant flower rather than three smaller ones.

When is the best time to plant dahlia tubers?

Dahlias should be planted in the spring once the soil has warmed to about 60°F and the danger of frost has completely passed. In most US regions, this is between late April and early June. Planting in warm soil ensures the tubers sprout quickly and reduces the risk of rot caused by cold, wet conditions. If you're not sure about your timing, check the Hardiness Zone Map for your local zone.

Do I really need to pinch my dahlia plants?

While not strictly required for the plant to survive, pinching is highly recommended for a better garden display. By snipping off the top of the main stem when the plant is about 12 inches tall, you encourage it to grow side branches. This results in a bushier plant that is less top-heavy and produces significantly more flowers throughout the season. For more support and pinching details, see How to Pinch and Stake Dahlias.

How often should I fertilize my dahlias?

Dahlias benefit from a regular feeding schedule. After the plants are about a foot tall, you can begin applying a water-soluble fertilizer every two weeks. Use a formula that is higher in phosphorus and potassium (like a tomato fertilizer) to encourage bloom production rather than just green leaf growth. Stop fertilizing about a month before the first expected frost. For a broader care checklist, see 8 Tips for Growing Better Dahlias.