Table of Contents
- Introduction
- Understanding Canna Lilies
- Choosing the Perfect Planting Site
- When to Plant Canna Lilies
- How to Plant Canna Rhizomes Step-by-Step
- Growing Canna Lilies in Containers
- Essential Summer Care and Maintenance
- Deadheading and Pruning for Better Blooms
- Lifting and Overwintering in Colder Climates
- Designing Your Garden with Canna Lilies
- Troubleshooting Common Canna Issues
- Conclusion
- FAQ
Introduction
Bringing a touch of the tropics to your backyard is one of the most rewarding ways to transform your summer landscape. Canna lilies are the undisputed champions of this look, offering massive, paddle-shaped leaves and vibrant flowers that stand tall throughout the heat of the season. Whether you have a sprawling garden bed or a small sunny balcony, these plants provide an architectural "wow" factor that is surprisingly easy to achieve.
At Longfield Gardens, we enjoy helping gardeners discover how these fast-growing plants can anchor a garden design. This guide is designed for anyone who wants to learn the best practices for success, from the first sprout in spring to the final cleanup in autumn. We will cover site selection, planting techniques, and simple maintenance steps to keep your garden looking its best.
Growing canna lilies is a straightforward way to add height and vibrant color to any garden space. By following a few simple steps, you can enjoy a lush, exotic display regardless of your previous gardening experience.
Understanding Canna Lilies
Canna lilies are not true lilies. They grow from thick, fleshy underground stems called rhizomes. These rhizomes store energy and moisture, which allows the plants to grow with incredible speed once the weather warms up. In a single season, some varieties can reach heights of six to eight feet, though there are many dwarf varieties that stay a more manageable two to three feet tall.
The foliage is often just as beautiful as the flowers. Depending on the variety, the leaves may be bright green, deep burgundy, or even striped with yellow and white. The flowers themselves come in a fiery palette of reds, oranges, yellows, and pinks. Because they are native to tropical and subtropical regions, they thrive in heat and humidity, making them a perfect choice for the mid-to-late summer garden in the United States.
In USDA hardiness zones 7 through 10, these plants are typically perennial and can stay in the ground year-round. In colder zones (3 through 6), they are treated as tender perennials. This means you plant them in the spring and either dig them up to store indoors for the winter or treat them as annuals and start with fresh rhizomes the following year.
Choosing the Perfect Planting Site
To get the most out of your plants, matching them to the right environment is the first step toward success. Cannas are high-energy plants that require a few specific conditions to reach their full potential.
Prioritize Sunlight
Sunlight is the primary fuel for a canna lily. For the most vibrant foliage and the highest number of blooms, choose a spot that receives at least six to eight hours of direct sunlight every day. While they can grow in partial shade, they often become "leggy," meaning the stems grow thin and tall as they stretch toward the light. This can lead to the plants flopping over during a heavy rain or windstorm.
Focus on Soil and Moisture
These plants are unique because they love water much more than most garden bulbs or perennials. In their native habitats, they often grow near the edges of ponds or in boggy areas. In your garden, they will perform best in rich, fertile soil that holds moisture well. If your soil is sandy, adding compost or well-rotted manure before planting will help improve its water-holding capacity.
While they appreciate consistent moisture, ensure the area has decent drainage so the rhizomes do not sit in stagnant, freezing water during the early spring. A spot that stays naturally damp but doesn't turn into a swamp after a light rain is ideal.
Wind Protection
Because of their large, sail-like leaves, cannas can sometimes be damaged by strong, sustained winds. The leaves may tear or "shred" at the edges, which doesn't hurt the plant's health but can make it look a bit untidy. If you live in a particularly windy area, planting them against a fence, a wall, or a backdrop of sturdy shrubs can provide the protection they need.
When to Plant Canna Lilies
Timing is everything when it comes to tropical plants. Cannas are very sensitive to cold temperatures and will not begin to grow until the environment is truly warm.
A good rule of thumb is to wait until the danger of frost has completely passed and the soil temperature has reached at least 60°F. For most gardeners, this coincides with the time you would normally plant tomatoes or peppers in the garden. Planting too early in cold, wet soil can cause the rhizomes to rot before they have a chance to wake up.
If you live in a region with a short growing season, you can give your plants a head start by potting them up indoors about four to six weeks before the last frost date. Place the pots in a warm, sunny window or under grow lights. By the time the weather is warm enough to move them outside, you will already have established plants ready to take off.
We ship our rhizomes according to your USDA hardiness zone so they arrive at the appropriate time for planting. If your shipment arrives and the ground is still frozen or too wet, keep the rhizomes in their packaging in a cool, dry place until the conditions improve.
How to Plant Canna Rhizomes Step-by-Step
Once the soil is warm and you have selected your site, planting is a quick and easy process. Follow these steps for the best results:
- Prepare the soil: Loosen the soil to a depth of about 10 to 12 inches. This makes it easier for the new roots to spread out and find nutrients.
- Dig the hole: Create a shallow hole about 3 to 4 inches deep.
- Position the rhizome: Lay the rhizome horizontally in the hole. Look for small bumps or "eyes"—these are the growth points. Point these eyes upward if possible, but don't worry if you can't tell which way is up; the plant will naturally find the surface.
- Space correctly: For standard tall varieties, space the rhizomes about 18 to 24 inches apart. This gives the large leaves room to unfurl without crowding the neighboring plants. For dwarf varieties, 12 inches is usually sufficient.
- Cover and firm: Fill the hole with soil and press down firmly with your hands to remove any large air pockets.
- Initial watering: Water the area thoroughly after planting to settle the soil around the rhizomes.
Key Takeaway: For the most vigorous growth, plant your rhizomes 3–4 inches deep in warm soil (60°F+) and space them about two feet apart to allow for their impressive summer spread.
Growing Canna Lilies in Containers
If you have limited space or want to add a vertical accent to your patio, canna lilies are excellent candidates for container gardening. Their upright habit makes them a perfect "thriller" in the center of a large pot.
Selecting the Right Pot
Because cannas grow quickly and produce a large root system, you need a substantial container. A pot with a diameter of at least 15 to 18 inches is ideal for a single rhizome. Ensure the pot has drainage holes at the bottom. While cannas love water, they do not want to sit in a pot that acts like a bucket without an exit for excess rain.
Potting Mix and Planting
Use a high-quality, well-draining potting soil rather than garden soil. Garden soil is too heavy for containers and can compact over time, making it hard for roots to breathe. Plant the rhizome at the same depth as you would in the ground (about 3 to 4 inches).
Container Maintenance
Plants in pots dry out much faster than those in the ground. During the peak of summer, you may need to water your container cannas every single day. They are also "heavy feeders," meaning they use up the nutrients in the potting soil quickly. Applying a water-soluble fertilizer every two weeks will help maintain their lush growth and consistent blooming.
Essential Summer Care and Maintenance
Once your cannas are established and growing, they require very little "work," but a few simple habits will keep them looking spectacular until the first frost.
Watering for Success
The most important rule for canna care is to keep them hydrated. If the soil becomes too dry, the leaf edges may turn brown and crispy. If you are experiencing a dry spell or a heatwave, give them a deep soaking twice a week. A layer of mulch, such as shredded bark or compost, around the base of the plants will help hold moisture in the soil and keep the roots cool.
Feeding Your Plants
Because cannas put on so much biomass in a single season, they need plenty of nutrients. If your soil is already rich, you might only need to apply a balanced, slow-release fertilizer once in the spring and again in mid-summer. If you notice the foliage looking a bit pale, an extra boost of compost or a liquid fertilizer can help.
Support and Staking
Most cannas have very sturdy, thick stems and do not require staking. However, if you have planted a very tall variety in a spot that gets a lot of wind, or if the soil is exceptionally loose, you might find that the plants lean. In these cases, a simple bamboo stake and a loose tie can provide the necessary support.
Deadheading and Pruning for Better Blooms
One of the easiest ways to keep your cannas looking fresh is through regular deadheading. Deadheading is the process of removing spent flowers before they have a chance to form seed pods.
How to Deadhead
Canna flowers grow in clusters on a single stalk. As individual flowers fade, you can simply snip them off. Once the entire flower stalk has finished blooming, look down the stem. You will often see a second flower bud lower down. Cut the old stalk back to just above that new bud. This encourages the plant to put its energy into new flowers rather than producing seeds.
Mid-Season "Haircut"
By late August, some of the older, lower leaves might start to look a little tired or tattered. You can remove these lower leaves by cutting them off near the main stem. This improves air circulation around the plant and keeps it looking tidy. If a plant ever looks completely overgrown or "ratty" due to weather, you can actually cut the whole thing back to about 6 inches. With plenty of water and food, it will quickly send up fresh, new growth.
What to do next:
- Check your plants weekly for faded blooms.
- Snip off old flower stalks to encourage secondary buds.
- Remove any damaged or yellowing lower leaves to keep the display looking tidy.
Lifting and Overwintering in Colder Climates
For gardeners in zones 3 through 6, cannas will not survive the freezing temperatures of winter in the ground. However, you can easily save your rhizomes to replant next year. This is a great way to save money and watch your collection grow, as the rhizomes will naturally multiply each season.
When to Dig
Wait until the first light frost kills the foliage. You will see the leaves turn black or brown and wilt. This is the signal that the plant has gone dormant. Cut the stems back to about 4 or 5 inches above the ground.
How to Lift and Store
- Dig carefully: Use a garden fork or shovel to lift the entire clump of rhizomes out of the ground. Be sure to start digging about a foot away from the stems to avoid slicing the rhizomes.
- Clean and dry: Gently 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." This toughens the outer skin and helps prevent rot.
- Pack them up: Place the rhizomes in a cardboard box or a paper bag. Cover them with slightly damp peat moss, vermiculite, or sawdust. This keeps them from drying out completely without making them wet enough to rot.
- Store cool: Keep the box in a cool, dark, frost-free place, such as a basement or crawl space. The ideal temperature is between 40°F and 50°F.
Check your stored rhizomes once or twice during the winter. If they look shriveled, lightly mist the packing material with water. If you see any soft or moldy spots, cut those sections away or discard the affected rhizome.
Designing Your Garden with Canna Lilies
Cannas are incredibly versatile in the landscape. Their bold texture makes them a perfect contrast to plants with fine-textured foliage or small flowers.
Create a Tropical Oasis
If you want your backyard to feel like a vacation spot, pair cannas with other large-leafed plants like elephant ears (Alocasia or Colocasia). Add some bright, sun-loving annuals like lantana, hibiscus, or zinnias around the base to fill in the space and provide even more color.
Vertical Interest in the Border
Because they are so tall, cannas are perfect for the "back of the border." They provide a solid wall of color that makes shorter perennials in front of them stand out. Try planting a dark-leaved canna variety, like 'Wyoming', behind a group of bright green ornamental grasses or silvery-blue hostas.
Privacy Screens
If you have a patio or a seating area that feels a bit too exposed, a row of tall cannas can create a beautiful, living privacy screen in just a few months. They grow thick enough to block the view from neighbors while providing a lush, green backdrop for your outdoor activities.
Troubleshooting Common Canna Issues
While cannas are generally "pest-free," there are a couple of things to look out for. Addressing these issues early is always easier than waiting until they spread.
Canna Leaf Rollers
The most common pest is the leaf roller, a small caterpillar that knits the leaves together before they unfurl, eating the tissue from the inside. If you see leaves that look stuck together or have rows of holes when they open, you likely have leaf rollers. The most effective solution is to apply a biological insecticide containing Bacillus thuringiensis (Bt). It is safe for pets and beneficial insects but stops the caterpillars from feeding.
Canna Rust
Rust is a fungal issue that appears as orange or yellow spots on the leaves. It usually happens in very humid weather with poor air circulation. To prevent it, ensure your plants have enough space between them. If you see affected leaves, remove and dispose of them (don't compost them) to stop the spores from spreading.
Lack of Blooms
If your cannas are growing plenty of leaves but no flowers, it is usually due to one of two things: not enough sun or not enough water. Ensure they aren't being shaded by nearby trees and increase your watering schedule. Sometimes, a late-planted canna just needs a little more time to reach maturity before it starts its flowering cycle.
Conclusion
Gardening with canna lilies is one of the easiest ways to bring high-impact color and drama to your outdoor space. Their resilience, rapid growth, and stunning variety make them a favorite for both beginners and experienced gardeners. Whether you are using them to create a private tropical retreat or simply to add some height to your flower beds, these plants rarely disappoint.
At Longfield Gardens, we take pride in providing high-quality rhizomes that are true to variety and ready to thrive. Remember that gardening is an ongoing journey of discovery, and each season brings new opportunities to learn what works best in your unique soil and climate. With a little bit of sunshine and plenty of water, your cannas will be the stars of your summer garden.
"The secret to a stunning canna display is simple: heat, water, and space. Give them these three things, and they will reward you with a tropical paradise all summer long."
Your Next Steps:
- Choose a sunny, moist spot in your garden for this year's planting.
- Wait for the soil to warm to 60°F before tucking your rhizomes into the earth.
- Keep the water flowing during the hot July and August days.
- Enjoy the spectacular, humming-bird-attracting blooms!
FAQ
How deep should I plant my canna lily rhizomes?
In most garden settings, you should plant canna rhizomes about 3 to 4 inches deep. This provides enough soil cover to protect the rhizome from drying out while allowing the new sprouts to reach the surface easily. If you are planting in a container, the same depth applies.
Do canna lilies come back every year?
Whether cannas come back depends on your local climate. They are perennials in USDA zones 7 through 10 and will return on their own each spring. In colder zones (3-6), the rhizomes will freeze and die if left in the ground over winter, so you must dig them up and store them indoors if you wish to grow the same plants the following year.
Can I grow canna lilies in the shade?
Cannas can survive in partial shade, but they will not perform at their best. Shade usually results in fewer flowers and foliage that is less vibrant. Additionally, the stalks may become weak and floppy as they "reach" for the sun. For the best results, aim for a spot with at least six hours of full sun.
Why are my canna lily leaves turning brown at the edges?
Brown, crispy edges on canna leaves are almost always a sign of "drought stress." Because cannas have such large leaves, they lose moisture quickly through transpiration. If the soil doesn't have enough water to replenish the plant, the edges of the leaves will dry out. Increasing your watering frequency and applying mulch can usually solve this problem.