Table of Contents
- Introduction
- Understanding the Canna Rhizome
- Identifying the Top and Bottom of a Canna Bulb
- How to Plant Canna Bulbs: A Step-by-Step Guide
- Planting Depth and Spacing for Maximum Impact
- When to Get Your Cannas in the Ground
- Starting Cannas in Containers
- Post-Planting Care: Sun, Water, and Food
- Common Canna Varieties for Your Garden
- Handling Growth Challenges
- Conclusion
- FAQ
Introduction
There is nothing quite like the sight of a canna lily unfurling its massive, tropical leaves in the heat of a summer afternoon. These statuesque plants bring an immediate sense of drama and lushness to any garden, regardless of whether you live in a warm southern climate or a cooler northern region. At Longfield Gardens, we love how cannas bridge the gap between architectural foliage and brilliant, showy blooms, making them one of the most rewarding additions to the summer landscape.
This guide is designed for home gardeners who want to take the guesswork out of starting these "horticultural titans." We will focus specifically on how to identify the right orientation for your canna rhizomes, how deep to plant them, and the simple steps you can take to ensure they grow tall and strong. Whether you are planting in a large backyard border or a decorative patio pot, getting the orientation right from the start sets your plants up for a successful season. For a broader overview, see our All About Cannas guide.
Understanding how these plants grow is the first step toward a garden filled with vibrant color and exotic texture. By following a few basic principles, you can transform your outdoor space into a tropical retreat.
Understanding the Canna Rhizome
Before we discuss which way to plant them, it is helpful to understand what you are actually holding in your hand. While most people refer to them as "canna bulbs," they are technically called rhizomes.
What is a Rhizome?
A rhizome is a thick, fleshy underground stem that grows horizontally just beneath the soil surface. Unlike a true bulb, such as a tulip, which is a self-contained "storage unit" of leaves and flower parts, a rhizome is a continuous growing structure. It stores energy and moisture for the plant, allowing it to produce those massive leaves and stalks throughout the summer.
When you receive your order from us, you will notice the rhizomes look like knobby, firm pieces of root. They are often irregularly shaped and may have smaller segments branching off. These segments are full of potential, as each one contains "eyes" that will eventually become the tall stems we admire.
Why Quality Matters
Starting with high-quality, firm rhizomes is the best way to ensure vigorous growth. At Longfield Gardens, we take care to provide rhizomes that are healthy and ready to sprout as soon as the conditions are right. A firm rhizome has the stored energy necessary to push through the soil and establish a strong root system before the summer heat arrives. Our 100% Quality Guarantee helps give gardeners extra confidence when they plant.
Key Takeaway: Canna "bulbs" are actually rhizomes, which are horizontal underground stems. Their thick, fleshy nature allows them to store plenty of energy for a spectacular summer display.
Identifying the Top and Bottom of a Canna Bulb
The most common question we hear from gardeners is how to tell the top from the bottom of a canna rhizome. Because they don't have the classic "pointed top and flat bottom" shape of a daffodil or tulip, it can feel a bit confusing at first. However, there are several easy-to-spot signs that will show you the way.
Look for the "Eyes"
The "eyes" are the most important part of the rhizome to identify. These are the small, pointed bumps or nodes where the new stems will emerge. They often look like little pink or white nubs, or they may be slightly more developed, appearing as small green shoots.
When you are ready to plant, these eyes should generally be pointed upward toward the sky. This gives the new growth the shortest and most direct path to the sunlight. If you see multiple eyes on a single rhizome, try to orient the piece so that the majority of those points are facing up.
Inspecting the Roots and Stems
If the eyes aren't obvious yet, look at the other features of the rhizome:
- Roots: You may see some dried, hair-like fibers on one side of the rhizome. These are the remnants of last year’s root system. Generally, the side with more of these fibers is the bottom.
- The Stem Stump: Sometimes, a rhizome will have a clearly cut, woody "stump" from the previous season's growth. This stump should face upward. The new sprouts will often form around the base of this old stem.
- Texture: One side of the rhizome might be smoother and flatter, while the other is knobby and irregular. The knobby side, which holds the growth points, is the top.
The Fail-Safe Horizontal Position
If you look at your canna rhizome and truly cannot tell which way is up, don't worry. The most natural way for a canna to grow is horizontally. In nature, these rhizomes spread out sideways just under the soil surface.
If you are in doubt, simply lay the rhizome flat on its side in the planting hole. Canna plants are incredibly resilient. The new shoots are programmed to grow toward the warmth of the sun, and the roots are programmed to grow toward moisture and gravity. Even if you plant it completely upside down, the plant will eventually find its way to the surface—it just might take a little longer to sprout.
How to Plant Canna Bulbs: A Step-by-Step Guide
Once you have identified the orientation, the actual planting process is quick and enjoyable. Planting cannas is one of those easy wins in the garden because the results are so dramatic.
Step 1: Prepare the Site
Choose a location that receives at least six to eight hours of direct sunlight. Cannas are tropical plants that love the heat, so the more sun they get, the better they will bloom. The soil should be well-drained. While cannas enjoy moisture, they do not like to sit in soggy, waterlogged soil, which can cause the rhizomes to struggle.
Step 2: Dig the Hole
Dig a hole or a trench about 4 to 6 inches deep. This depth protects the rhizome from temperature fluctuations and provides a sturdy anchor for the tall stems that will grow later in the season. If you are planting in a group, spacing is important. Tall varieties should be spaced about 2 feet apart, while dwarf or medium varieties can be spaced 12 to 18 inches apart.
Step 3: Position the Rhizome
Place the rhizome in the hole. As we discussed, aim for the "eyes" to face upward or lay the rhizome horizontally. If you are using an auger or a bulb planter, ensure the hole is wide enough so you don't have to force the rhizome in, which could snap off the delicate eyes.
Step 4: Cover and Firm the Soil
Fill the hole with soil and gently press down with your hands to remove any large air pockets. You don't need to pack it tightly; just a light firming will do. This ensures the rhizome has good contact with the soil, which helps it absorb moisture.
Step 5: Water Well
Water the area thoroughly right after planting. This "settles" the soil around the rhizome and signals to the plant that it is time to wake up and start growing. After this initial watering, you can wait until you see the first green shoots before you begin a regular watering schedule.
What to Do Next:
- Choose a sunny spot with at least 6 hours of light.
- Identify the "eyes" or growth points on your rhizomes.
- Dig holes 4-6 inches deep and space them according to the variety's mature size.
- Place rhizomes with eyes up or horizontally.
- Water once to settle the soil.
Planting Depth and Spacing for Maximum Impact
While orientation is important, the depth and spacing of your cannas play a huge role in how they look once they reach maturity. Because cannas grow quite large, they need their personal space to look their best and prevent issues with air circulation.
Finding the Right Depth
A planting depth of 4 to 6 inches is the "sweet spot" for most cannas. If you plant them too shallowly, the tall stalks might lean or fall over during a summer thunderstorm because they lack a deep enough anchor. If you plant them too deeply, they will take a very long time to emerge, and in some cases, the soil might stay too cool for the rhizome to sprout properly.
If you are gardening in a region with very sandy soil, you can lean toward the deeper end (6 inches). In heavy clay soil, sticking to 4 inches is often better to ensure the shoots can easily reach the surface.
Spacing for Garden Design
Cannas are often used to create a living screen or a bold backdrop in a garden bed. To achieve a "wall of color" effect, plant them slightly closer together—about 12 to 15 inches apart. For individual specimen plants where you want to appreciate the shape of the foliage and flowers, give them a full 2 feet of space.
If you are planting dwarf varieties, which typically stay under 3 feet tall, you can space them as close as 10 to 12 inches. This creates a dense, lush carpet of tropical color that works beautifully at the front of a border.
When to Get Your Cannas in the Ground
Timing is often more important than the exact planting technique. Since cannas are tropical plants, they have no tolerance for frost and very little patience for cold soil.
Wait for the Warmth
The golden rule for planting cannas is to wait until the soil has warmed to at least 60°F. This usually happens around the same time you would plant your tomatoes or peppers outdoors. In most regions, this is several weeks after the last frost date.
If you plant them when the soil is still cold and damp, the rhizomes will simply sit dormant. They won't start growing until the ground warms up, so there is no real advantage to planting them too early. In fact, warm soil is the "trigger" that tells the canna it is safe to grow.
Shipping and Arrival
When you order from us, we time our shipping based on your shipping information. This means your cannas should arrive right around the time it is safe to start thinking about planting. If they arrive and your weather is still unseasonably cold, you can keep the rhizomes in their original packaging in a cool, dry place like a garage or basement until the soil warms up.
If you are unsure about your local climate, our Hardiness Zone Map can help you match planting time to your region.
Starting Cannas in Containers
If you live in a northern climate with a short growing season, or if you simply want to enjoy cannas on your deck or patio, containers are an excellent choice. How to Grow Summer Bulbs in Containers offers more helpful tips for getting them off to a strong start.
Why Use Containers?
Starting cannas in pots indoors about four to six weeks before the last frost gives you a "head start" on the season. This means you will have established plants ready to bloom much earlier in the summer than if you waited to plant them directly in the ground.
Choosing the Right Pot
Cannas have vigorous root systems and can grow quite large, so they need plenty of room. A pot that is at least 12 to 18 inches in diameter is ideal for a single rhizome. Ensure the container has drainage holes at the bottom.
The Planting Process for Pots
- Soil: Use a high-quality potting mix. Avoid using garden soil, which can be too heavy and might not drain well enough for a container.
- Depth: Plant the rhizome about 3 to 4 inches deep in the pot. This leaves enough room for the roots to grow downward while keeping the rhizome securely covered.
- Watering: Water sparingly at first. Once you see the first green spike poking through the soil, you can increase the frequency of watering.
- Moving Outdoors: When the nighttime temperatures are consistently above 50°F, you can move your pots outside. Start by placing them in a sheltered, shady spot for a few days to "harden them off" before moving them into full sun.
Key Takeaway: Containers are a great way to jumpstart the season. Use a large pot, quality potting mix, and plant the rhizomes 3-4 inches deep for the best results.
Post-Planting Care: Sun, Water, and Food
Once your cannas have sprouted and are reaching for the sky, their needs are relatively simple. Because they grow so fast—some varieties can reach 6 to 8 feet in a single season—they are "heavy feeders."
Sunlight and Water
Cannas are solar-powered. To get the most vibrant flower colors and the lushest foliage, ensure they stay in a spot with maximum sun.
Water is equally important. Cannas are one of the few garden plants that can actually handle "wet feet" once they are growing vigorously. During the heat of the summer, they appreciate consistent moisture. If the soil dries out completely, the edges of the leaves may turn brown. A layer of mulch around the base of the plants helps retain moisture and keeps the roots cool.
For more planting inspiration, see Fresh Ideas for Growing Cannas.
Feeding Your Cannas
Because cannas produce so much biomass in a short time, they benefit from regular fertilizing. A balanced, slow-release fertilizer applied at planting time is a great start. You can also follow up with a water-soluble fertilizer every few into the growing season to keep the blooms coming.
Deadheading for More Blooms
As the flowers fade, you can remove the spent blooms. This process, called deadheading, prevents the plant from putting energy into producing seeds and encourages it to produce more flower spikes. Just be careful not to snip off the new buds that are often forming right next to the old ones!
Common Canna Varieties for Your Garden
Selecting the right variety depends on the space you have and the "look" you want to achieve. At Longfield Gardens, we offer a range of sizes and colors to suit every garden style.
If you're comparing plant heights, start with our tall cannas.
For smaller-space planting, our medium cannas collection is a good next stop.
- Tall Varieties: These are the classics, reaching 5 to 8 feet tall. Varieties like The President (bright red) or 'Richard Wallace' (sunny yellow) are perfect for back-of-the-border height.
- Dwarf and Compact Varieties: If you have a smaller space or are planting in containers, look for varieties that stay between 2 and 3 feet tall. City of Portland and 'Lucifer' are excellent choices that provide big color without taking up too much room.
- Stunning Foliage: Some cannas are grown as much for their leaves as their flowers. Tropicanna (also known as Phaison) features incredible striped leaves in shades of orange, green, and burgundy. 'Wyoming' offers deep bronze foliage that contrasts beautifully with its bright orange blooms.
Handling Growth Challenges
Cannas are generally very healthy plants, but there are a few things to keep an eye on as they grow.
Slow Sprouting
If your cannas haven't appeared after three weeks, don't panic. They are notorious for being slow starters, especially if the soil isn't quite warm enough yet. As long as the rhizome is firm and not mushy, it is fine. Once the heat of summer truly kicks in, they will often grow several inches in a single week.
Wind Damage
Because canna leaves are so large and soft, they can sometimes be torn by high winds. This doesn't hurt the health of the plant, but it can make it look a bit "shredded." If you live in a very windy area, try to plant your cannas near a fence, a wall, or a group of sturdy shrubs that can act as a windbreak.
Canna Leaf Rollers
In some regions, a small caterpillar known as a leaf roller may try to zip the leaves shut. If you see leaves that won't unfurl or have small holes in a row, you can simply unroll the leaf and remove the caterpillar by hand. Keeping the garden clean and removing old foliage at the end of the year helps reduce pest pressure for the following season.
Conclusion
Planting canna bulbs is a straightforward and rewarding process that brings a touch of the tropics to any backyard. By identifying the "eyes" and planting your rhizomes about 4 to 6 inches deep in warm, sun-drenched soil, you are giving these plants exactly what they need to thrive. Whether you plant them vertically with the eyes up or lay them horizontally, their natural resilience and drive to reach the sun will almost always lead to success.
Remember that patience is a virtue when it comes to cannas; they may take their time to wake up, but once they do, their growth is truly spectacular. We are here to help you every step of the way, from selecting the perfect varieties to providing the tips you need for a beautiful season.
- Wait for warm soil: Ensure the ground is at least 60°F before planting.
- Orientation: Plant with eyes up or horizontally for the best results.
- Depth and Spacing: Dig holes 4-6 inches deep and space plants 1-2 feet apart.
- Consistent Care: Provide plenty of sun, water, and occasional fertilizer for maximum growth.
"Gardening with cannas is all about embracing the bold. These plants aren't shy, and with just a little bit of care during the planting phase, they will reward you with a summer-long festival of color and texture."
For your next step, browse our premium canna rhizomes and start planning your own tropical oasis. Happy planting!
FAQ
Does it matter if I plant canna rhizomes upside down?
While it is best to plant cannas with the "eyes" facing up or horizontally, planting them upside down is not a disaster. The plant will eventually sense the warmth of the sun and the pull of gravity, causing the shoots to grow around the rhizome and reach the surface. It may simply take a week or two longer for the plant to emerge from the soil.
How deep should I plant canna bulbs in a pot?
When planting cannas in containers, aim for a depth of 3 to 4 inches. This provides enough soil on top to keep the rhizome moist and stable while leaving plenty of room at the bottom of the pot for the roots to expand. Ensure the pot is large enough to accommodate the vigorous growth of the variety you have chosen.
Why are my canna bulbs taking so long to sprout?
Cannas are heat-loving plants and can be very slow to sprout if the soil temperature is below 60°F. If your garden is still waking up from spring, the rhizomes may stay dormant for several weeks. Once the weather stays consistently warm, you will see rapid growth. Starting them indoors in pots is a great way to speed up this process.
Should I soak canna rhizomes before planting?
Soaking is not strictly necessary, but some gardeners find that soaking the rhizomes in lukewarm water for a few hours before planting helps "wake them up" and rehydrate them. If you choose to skip this step, simply ensure that you water the area thoroughly immediately after planting to settle the soil and trigger growth.