Introduction
There is something undeniably exciting about watching a tropical garden come to life in your own backyard. Canna lilies (Canna x generalis) are the champions of this transformation, offering bold, architectural foliage and vibrant flowers that make any space feel like a private resort. Whether you are a seasoned pro or just starting your first garden, these plants are remarkably rewarding because they grow so quickly.
At Longfield Gardens, we believe that every yard deserves a touch of the tropics. Canna lilies are easy to grow from tubers, which are technically called rhizomes, and they provide a massive amount of color for very little work. This guide will walk you through everything you need to know about selecting, planting, and caring for these spectacular summer bloomers.
We will cover the best timing for planting, how to prepare your soil, and the simple steps to keep your cannas thriving all season long. By focusing on a few basic needs like sun and water, you can enjoy a lush, colorful landscape from midsummer through the first frost.
Understanding Canna Lily Tubers
Before you get your hands in the dirt, it is helpful to know what you are planting. While many people call them "bulbs" or "tubers," canna lilies grow from rhizomes. A rhizome is a thick, fleshy underground stem that grows horizontally just beneath the soil surface.
When you receive your canna rhizomes from us, they will look like sturdy, starchy roots. You may notice small bumps or pointed tips on the surface. These are called "eyes," and they are the points where the new stems will emerge. A healthy rhizome should feel firm and heavy for its size.
Canna lilies are native to tropical and subtropical regions. This means they love heat and plenty of moisture. Because they are not cold-hardy in most of the United States, they are often treated as "summer bulbs." In warmer climates, they can stay in the ground year-round. In cooler zones, gardeners simply lift the tubers in the fall and store them indoors for the winter.
Choosing the Right Variety for Your Garden
One of the best things about growing canna lily from tubers is the incredible variety of sizes and colors available. There is a canna for every garden style, from compact plants for small patios to towering giants that create a natural privacy screen. For more bold options, browse our Tall Cannas collection.
Compact and Dwarf Varieties
If you have a small suburban garden or want to grow cannas in pots, compact varieties are a perfect choice. These typically reach 2 to 4 feet in height. They offer the same tropical look as their larger cousins but fit comfortably in tighter spaces.
- Canna ‘Orange Punch’: This is a fantastic compact cultivar that grows to about 4 feet tall. It produces clusters of bright orange flowers with yellow streaks.
- Canna ‘Salmon Pink’: A shorter option reaching about 3 feet, this variety features soft pink blooms that contrast beautifully against dark green foliage.
- Canna ‘Madame Butterfly’: This variety is prized for its large, salmon-pink blooms and manageable size.
Tall and Dramatic Varieties
For the back of a flower border or to hide a fence, taller cannas are unmatched. These varieties can reach 5 to 8 feet in height in a single season.
- Canna ‘Black Knight’: This variety is famous for its stunning, dark burgundy-to-black foliage and deep red flowers.
- Canna ‘Stuttgart’: A favorite for foliage lovers, this variety features green and white variegated leaves that look striking even when the plant is not in bloom.
- Canna ‘Striped Beauty’: This variety offers yellow flowers and green leaves with bright yellow stripes.
Foliage That Steals the Show
While the flowers are beautiful, many gardeners grow cannas specifically for their leaves. You can find foliage in shades of bright green, bronze, deep mauve, and even multicolored patterns.
- Canna ‘Tropical Bronze’: Features scarlet red flowers and deep bronze foliage.
- Canna ‘Inferno’: Known for its multicolored foliage and vivid red blooms.
- Canna ‘Crimson Beauty’: A classic choice with deep red flowers and clean green foliage.
Key Takeaway: Match the mature height of the canna variety to your space. Use dwarf varieties for containers and tall varieties for back-of-the-border drama.
When to Plant Canna Lily Tubers
Timing is everything when it comes to tropical plants. Canna lilies cannot tolerate frost and will not grow in cold soil. For the best start, wait until the soil temperature has warmed to at least 60°F. Check your USDA hardiness zone before planting.
Planting Outdoors
In most regions, this means planting outdoors in late spring or early summer, around the same time you would plant tomatoes or peppers. If you plant them too early in cold, wet soil, the rhizomes may sit dormant or struggle to establish roots. A soil thermometer is a helpful tool to take the guesswork out of planting time.
Starting Early Indoors
If you live in a northern climate with a short growing season, you can give your cannas a head start by planting them indoors. Start the rhizomes in pots about 6 to 8 weeks before the average last frost date. By the time the weather warms up, you will have established plants ready to move into the garden. This often results in earlier blooms and a much larger plant by midsummer.
Selecting the Best Planting Site
To get the most out of your canna lily tubers, you need to find the right spot. These plants are not shy about their needs: they want sun, food, and water. Our best growing conditions guide can help you plan the right site.
Sunlight Requirements
Cannas are sun worshippers. For the best flower production and the most vibrant foliage colors, they need full sun. This means at least 6 to 8 hours of direct sunlight every day. If they are planted in too much shade, they will become tall and "leggy" as they stretch for the light, and they may not bloom at all.
Soil and Drainage
While cannas love water, they do not like to sit in stagnant, soggy mud. "Drainage" refers to how fast water leaves the soil. To check your drainage, watch your planting spot after a heavy rain. If water puddles remain for more than 5 or 6 hours, the soil may be too heavy.
You can improve drainage by adding organic matter like compost, composted manure, or shredded bark. This raises the soil level and creates a fluffier texture that allows roots to breathe. Cannas prefer a slightly acidic to neutral soil pH (around 6.0 to 6.5).
Wind Protection
Because cannas have large, broad leaves, they can act like sails in high winds. If your garden is very windy, the leaves may tear or become ragged. If possible, plant your cannas near a fence, a wall, or other sturdy plants that can provide a bit of a windbreak.
How to Plant Canna Lily Tubers Step-by-Step
Once the weather is warm and you have found the perfect spot, it is time to plant. Following these simple steps ensures your rhizomes are positioned for success. For spacing details in beds and pots, see our canna spacing guide.
1. Prepare the Soil
Loosen the soil in your planting area to a depth of about 12 inches. This makes it easier for the new roots to spread. Mix in a few inches of compost to provide a slow-release source of nutrients.
2. Check the Rhizome Orientation
Look at your canna rhizome to find the "eyes" or the remains of last year’s stem. You want to plant the rhizome horizontally with the eyes or the stem stump facing upward. If you cannot tell which side is up, do not worry—cannas are resilient and will eventually find their way to the surface, though it may take a little longer.
3. Dig the Hole
Dig a hole that is 4 to 6 inches deep. If you are planting multiple cannas, space them based on their variety.
- Dwarf Varieties: Space 12 inches apart.
- Tall Varieties: Space 18 to 24 inches apart.
4. Set and Cover
Place the rhizome in the hole and cover it with soil. Press down gently with your hands to remove any large air pockets, but do not pack the soil too tightly.
5. Water Thoroughly
Water the area well immediately after planting. This settles the soil around the rhizome and "wakes up" the plant. After this initial watering, be patient. It can take three weeks or more to see the first sprouts emerge from the ground.
What to do next:
- Check the local frost dates for your area.
- Purchase high-quality compost to amend your soil.
- Ensure you have a sunny spot with at least 6 hours of light.
- Label each planting spot so you know which variety is which.
Growing Canna Lilies in Containers
If you have limited garden space or want to decorate a patio, canna lilies grow beautifully in pots. The process is very similar to planting in the ground, with a few extra considerations. See how many canna bulbs you should plant together in pots.
Choosing the Right Pot
Cannas grow fast and develop large root systems. Use a container that is at least 15 to 18 inches in diameter for a single rhizome. Ensure the pot has plenty of drainage holes at the bottom. If the roots sit in water for too long inside a pot, the rhizome can rot.
Using Potting Mix
Always use a high-quality potting mix designed for containers rather than garden soil. Potting mix is lighter and contains ingredients like perlite or coco coir to keep the soil fluffy. This is vital for "drainage," as garden soil can become too compacted in a pot.
Maintenance in Containers
Plants in containers dry out much faster than those in the ground. During the heat of summer, you may need to water your potted cannas every day. Because you are watering frequently, nutrients also wash out of the soil faster. Use a balanced liquid fertilizer every 2 to 4 weeks to keep the plants well-fed.
Ongoing Care and Maintenance
Once your cannas are growing vigorously, they are relatively low-maintenance. However, a little extra attention can lead to a much longer blooming season. More container and spacing tips for cannas are here.
Watering Correctly
Cannas are "thirsty" plants. They thrive when the soil is consistently moist. During dry spells or the peak of summer heat, provide a deep soaking once or twice a week. If the leaves begin to curl or look wilted, it is usually a sign that they need more water. Mulching around the base of the plants with straw or shredded leaves can help hold moisture in the soil.
Fertilizing for Big Blooms
Since cannas grow so much biomass in a single season, they are heavy feeders. They benefit from a balanced, slow-release fertilizer applied at planting time. You can follow this up with another application in midsummer. Alternatively, using a water-soluble fertilizer every few weeks will support continuous flower production and lush leaf growth.
Bloom Optimization and No-Flower Causes
If your cannas are producing plenty of foliage but few or no flowers, several factors might be at play. First, ensure they are receiving at least 6 to 8 hours of direct sun; insufficient light is the most common cause of poor blooming. Second, avoid fertilizers that are too high in nitrogen, as these promote leaves at the expense of flowers. Lastly, check for overcrowding. If your canna tubers have multiplied over several years and are too close together, they may stop flowering. Dividing the clumps in spring or fall can rejuvenate the plant and bring back the blooms.
Deadheading
To keep your cannas looking tidy and encourage more flowers, you should practice "deadheading." This means removing the spent flowers before they turn into seed pods.
- Canna stems produce several flowers on a single spike.
- Snip off only the individual faded flower where it meets the stem.
- Once the entire flower spike has finished blooming, you can cut that specific stem back to the next set of leaves.
- Be careful not to cut off any new flower buds that may be forming lower down on the same stem.
Managing Pests and Diseases
Cannas are generally quite hardy, but they can occasionally attract pests. The canna leafroller is a common problem; these caterpillars roll the leaves shut with silk and eat the foliage from the inside. Look for small holes in new leaves or leaves that fail to unfurl. You may also see aphids or spider mites, which are small insects that feed on leaf sap. A strong spray of water from a garden hose can knock them off, or you can use insecticidal soap.
Diseases like rhizome rot can occur if the tubers are kept too wet in poorly drained soil or stored improperly during winter. Affected rhizomes will feel mushy and may have a foul smell. To prevent this, always ensure your planting site has excellent drainage and avoid overwatering during the early spring when the plant is just starting to grow.
Troubleshooting Canna Tuber Issues
Sometimes, your canna tubers may struggle to get started. If your rhizomes have not sprouted after 3 or 4 weeks, don't panic, but do check the following:
Why won't my canna tubers sprout?
The most frequent cause is soil temperature. If the ground is below 60°F, the rhizomes will stay dormant. If you've had a cold, wet spring, they may be slow to emerge. Check the planting depth; if they are deeper than 6 inches, they will take longer to reach the surface. Gently brush away some soil to check the rhizome. If it is still firm, it is simply waiting for more heat. If it is soft and mushy, it has likely succumbed to rhizome rot and needs to be replaced.
Dealing with slow growth
If your plants have emerged but are growing very slowly, they may need more "food" or more sun. Ensure you are using a balanced fertilizer and that the plants aren't being shaded by nearby trees or structures.
How to Divide Canna Lily Rhizomes
As your cannas grow, they will naturally form large, expanding clumps of rhizomes. To maintain the vigor of the plant and prevent overcrowding, we recommend dividing them every 3 to 5 years.
- When to Divide: The best time to divide canna tubers is in the spring before planting, or in the fall when you are lifting them for winter storage.
- Lift the Clump: Carefully dig around the entire clump and lift it from the ground.
- Separate the Rhizomes: Use your hands or a clean, sharp knife to break the clump into smaller sections. Each new division must have at least one or two "eyes" (growing points) to produce a new plant.
- Discard Old Material: Throw away any parts of the rhizome that look shriveled, hollow, or soft.
- Replant: Plant the new divisions immediately if it is spring, or prepare them for storage if it is fall.
End-of-Season Care and Overwintering
What you do at the end of the season depends entirely on your USDA hardiness zone. Canna lilies are tropical, and their rhizomes will freeze and die if the ground turns to ice. This process, often called canna lily winter care, ensures your plants return year after year. Learn more about winter survival and cold hardiness for cannas.
Warmer Climates (Zones 7-11)
In Zones 8 through 11, cannas can stay in the ground all year. In Zone 7, they often survive if the winter is mild and they are protected with a thick layer of mulch. Once the first frost hits and turns the foliage brown, cut the stems down to about 4 inches above the ground. Cover the area with 4 to 6 inches of straw or leaves to act as insulation.
Cooler Climates (Zones 6 and Below)
In colder regions, you must "lift" the tubers if you want to grow them again next year.
- Wait for Frost: Wait until the first light frost kills the foliage. This tells the plant to move its energy down into the rhizome.
- Cut Back: Cut the stems down to about 4 to 6 inches.
- Dig Carefully: Use a garden fork or shovel to gently lift the clump out of the ground. Start digging about a foot away from the stem to avoid slicing through the rhizomes.
- Clean and Dry: Shake off the excess soil. Let the rhizomes sit in a dry, shaded area (like a garage or porch) for a few days to "cure" or toughen up.
- Store: Place the rhizomes in a cardboard box or paper bag filled with peat moss, vermiculite, or wood shavings. Store them in a cool, dark, dry place that stays between 40°F and 50°F. A basement or an attached garage is usually perfect.
Overwintering Potted Cannas
If you grow cannas in containers, you have two options for winter. You can bring the entire pot into a frost-free area like a basement or garage and let the plant go dormant. In this case, stop watering and cut the foliage back after the first frost. Alternatively, you can try keeping them as live plants indoors if you have a very bright, sunny window or grow lights, though they often prefer a dormant rest period. If storing them dormant in the pot, check the soil once a month; it should be barely moist—never bone dry, but never wet enough to cause rhizome rot.
Key Takeaway: If you live in a cold climate, lifting canna rhizomes is a simple way to save money and enjoy your favorite varieties year after year.
Realistic Expectations for Your Cannas
While cannas are easy to grow, it is important to remember that every garden is different. The final height and bloom time of your plants will depend on your local weather, soil quality, and how much sun they receive.
In a very hot, long summer, cannas may reach their maximum height and bloom for months. in a cool, cloudy summer, they may grow a bit slower. Don't be discouraged if your plants take a few weeks to start growing after planting—they are simply waiting for the soil to hit that perfect "tropical" temperature.
Also, keep in mind that many garden plants, including canna lilies, can be toxic if eaten by pets or children. It is always a good idea to keep your tubers and plants out of reach of curious nibblers.
Summary of Success
Growing canna lily from tubers is one of the fastest ways to add massive color and texture to your yard. By following the "Right Plant, Right Place" rule, you ensure these tropical beauties have the sun and water they need to thrive. Find your shipping information and zone timing here.
- Wait for warm soil (60°F) before planting.
- Choose a spot with at least 6-8 hours of direct sun.
- Plant rhizomes 4-6 inches deep and keep the soil moist.
- Fertilize regularly to support their rapid growth.
- In cold zones, lift and store the rhizomes after the first frost.
At Longfield Gardens, we want to help you create a garden that brings you joy every day. With their lush leaves and stunning flowers, canna lilies are a simple way to turn your backyard into a beautiful escape. Whether you plant them in a large garden bed or a single patio pot, the reward is well worth the minimal effort.
"Gardening is a rewarding journey, and canna lilies are the perfect companions for anyone looking to add high-impact color with very little stress."
FAQ
How long does it take for canna lily tubers to sprout?
It typically takes about 2 to 3 weeks for canna lilies to sprout after planting, but this depends heavily on soil temperature. If the soil is cool, they may sit dormant for up to a month. You can speed up this process by starting them indoors in pots 6 to 8 weeks before the last frost.
Can I grow canna lilies in full shade?
No, canna lilies generally require full sun to perform their best. While they may survive in partial shade, they will often become tall and weak, and flower production will be significantly reduced. For the best foliage color and the most blooms, aim for at least 6 to 8 hours of direct sunlight.
Do I need to 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 can help "wake them up." If your rhizomes feel very dry or shriveled, a short soak can help rehydrate them. If they feel firm and hydrated, you can plant them directly into moist soil.
Why are my canna lily leaves turning brown on the edges?
Brown edges on canna leaves are usually caused by either lack of water or "windburn." Cannas have very large leaves that lose moisture quickly, so they need consistently damp soil. If the soil is dry, the edges will crisp up. Similarly, high winds can damage the delicate leaf tissue, so providing a windbreak can help keep them looking pristine.
How do I know if my stored rhizomes are still good?
Before planting in the spring, inspect your stored tubers. A healthy rhizome should feel firm and heavy. If a rhizome feels light, airy, or hollow, it has likely dried out too much. If it is soft, slimy, or has a distinct foul odor, it has developed rhizome rot and should be discarded. Look for the "eyes" or small pinkish-white bumps which indicate the plant is ready to grow.
