Table of Contents
- Introduction
- Understanding Canna Rhizomes
- Choosing the Right Canna Varieties
- When to Start Your Canna Journey
- How to Start Cannas in Pots
- Preparing the Garden Site
- Planting Rhizomes in the Garden
- Summer Care and Maintenance
- Managing the Blooms
- Growing Cannas in Containers
- Fall Care and Overwintering
- Conclusion
- FAQ
Introduction
Imagine stepping into your backyard and feeling as though you have been transported to a lush, tropical paradise. Cannas are the secret to achieving this high-impact look with minimal effort. Their oversized, paddle-shaped leaves and vibrant, jewel-toned flowers bring an undeniable energy to any summer landscape. At Longfield Gardens, we love how these fast-growing plants can transform a standard garden bed into a spectacular display in just one season.
Growing these showstoppers from rhizomes is a rewarding process that fits into almost any gardening schedule. Whether you have a sprawling suburban lawn or a collection of pots on a sunny balcony, cannas are incredibly versatile and resilient. For a deeper overview of planning, planting, and caring for these plants, see All About Cannas. This guide will walk you through everything you need to know, from selecting the best varieties to successfully overwintering your plants for next year. By following a few simple steps, you can enjoy a season full of bold color and architectural beauty.
Understanding Canna Rhizomes
Before you start digging, it is helpful to understand what you are planting. While many people refer to them as "bulbs," cannas actually grow from rhizomes. A rhizome is a thick, fleshy underground stem that grows horizontally. It acts as a storage unit for the plant, holding the energy and nutrients needed to produce those massive leaves and tall flower spikes.
When you receive your canna rhizomes from us, you will notice they look like thick, starchy roots with small bumps or points. These points are called "eyes," and they are the growth buds from which the new stems will emerge. If you want a more detailed explanation of canna root structure, Do Canna Lilies Have Bulbs? Identifying Canna Root Systems is a helpful read. Healthy rhizomes should feel firm to the touch, similar to a fresh potato. If you see small sprouts already starting to grow, do not worry. This is a sign that the plant is eager to get started and is perfectly healthy to plant.
Choosing the Right Canna Varieties
One of the most exciting parts of growing cannas is the sheer variety of colors and sizes available. Because we maintain trial gardens to evaluate performance, we know that choosing the right variety for your specific space makes a big difference.
Foliage That Steals the Show
In many cases, the leaves of a canna lily are just as beautiful as the flowers. You can find varieties with solid green, deep burgundy, or even variegated foliage.
- Green Foliage: These provide a classic, clean look that makes the bright flower colors pop.
- Bronze and Burgundy: Varieties like 'Tropical Bronze' or 'Black Knight' offer dark, moody leaves that add incredible contrast to the garden, even before the flowers appear.
- Variegated Patterns: Some cultivars, like 'Stuttgart' or 'Striped Beauty', feature stripes of white, yellow, or orange across the green leaves, creating a high-fashion look in the garden.
Selecting by Size
Cannas come in a wide range of heights, so it is important to match the plant to its location. For taller plantings, browse Tall Cannas.
- Dwarf Varieties: These typically stay between 2 and 3 feet tall. They are the perfect choice for containers or the front of a garden border.
- Standard Varieties: These grow 4 to 6 feet tall and work well in the middle of a flower bed where they can provide a solid wall of color.
- Giant Varieties: Some cannas can reach 8 feet or more in a single season. These are fantastic for creating temporary privacy screens or as a dramatic focal point in a large landscape.
Key Takeaway: Always check the expected mature height of your variety before planting. Placing a giant variety at the front of a border can quickly hide your other favorite perennials.
When to Start Your Canna Journey
Timing is everything when it comes to tropical plants. Cannas love heat and have a very low tolerance for cold. Because they require a long growing season to reach their full potential, many gardeners choose to "wake them up" early.
Starting Indoors
If you live in a northern climate with a short summer, we recommend starting your rhizomes in pots indoors. You can do this about 6 to 8 weeks before the last expected frost in your area. For planting-time guidance, When Can You Plant Canna Bulbs? Expert Timing Guide is useful. This gives the plants a head start, ensuring they are already several inches tall by the time the weather is warm enough to move them outside.
Planting Directly Outdoors
If you prefer to plant directly into the ground, you must wait until the soil has warmed significantly. A good rule of thumb is to wait until you are ready to plant your tomatoes. The soil temperature should be at least 60°F. If the soil is too cold and wet, the rhizomes may sit dormant for a long time or struggle to get started. Patience during the spring pays off with much faster growth once the summer heat arrives.
How to Start Cannas in Pots
Starting your rhizomes in containers is a simple way to guarantee success. This method allows you to control the environment and protect the young sprouts from unpredictable spring weather.
Step 1: Choose the Right Container
For starting indoors, a 1-gallon pot is usually sufficient for a single rhizome. Ensure the pot has plenty of drainage holes at the bottom. Cannas like moisture, but they do not like to sit in stagnant water.
Step 2: Prepare the Soil
Use a high-quality, well-draining potting mix. You can enhance the drainage by adding a bit of perlite or coarse sand. Fill the pot about two-thirds of the way with the mix.
Step 3: Planting Depth and Direction
Place the rhizome horizontally on top of the soil. Look for the "eyes" or the remains of last year’s stem and make sure they are facing upward. Cover the rhizome with about 2 to 4 inches of soil. For more on planting depth, see How Deep to Plant a Canna Bulb: A Guide for Big Blooms. Press down lightly to ensure the soil is in contact with the rhizome, but do not pack it too tightly.
Step 4: Initial Care
Water the pot thoroughly after planting. Place the container in a warm, bright spot. A sunny windowsill or a spot under grow lights works perfectly. For the first few weeks, water sparingly—only when the top inch of soil feels dry. Once you see green shoots emerging, you can begin to water more regularly.
What to do next:
- Check your local frost dates to time your indoor start correctly.
- Purchase a high-quality potting mix designed for containers.
- Find a warm, sunny spot in your home for the pots.
- Label each pot so you know which variety is which.
Preparing the Garden Site
When it is finally time to move your plants outdoors, choosing the right location is the most important decision you will make. Cannas are not shy about their needs: they want sun, food, and water.
Sun Exposure
To get the best flowers and the most vibrant leaf colors, cannas need full sun. This means at least 6 to 8 hours of direct sunlight every day. While they can grow in partial shade, they will likely be taller and "leggier," with fewer blooms.
Soil Quality and Drainage
Cannas are "heavy feeders," meaning they thrive in rich soil that is high in organic matter. Before planting, work a few inches of compost or well-rotted manure into the soil. This provides a slow-release source of nutrients and helps the soil retain the moisture these plants crave. While they love water, they still need the soil to drain. If your garden has heavy clay that stays soggy for days, consider planting in raised beds or large containers.
Wind Protection
Because cannas have large, soft leaves, they can catch the wind like a sail. In very windy areas, the leaves may tatter or tear at the edges. If possible, plant them near a fence, a wall, or a line of sturdy shrubs to provide a bit of a windbreak.
Planting Rhizomes in the Garden
Once the danger of frost has passed and the soil is warm, you can move your indoor-started plants or plant dormant rhizomes directly into the ground.
Spacing for Success
Cannas grow quickly and need room to breathe. For a fuller planting guide, Spacing Canna Bulbs: Essential Tips for a Lush Garden is a useful reference. Space dwarf varieties about 1.5 feet apart and larger varieties at least 2 feet apart. This spacing ensures that each plant gets enough sunlight and that air can circulate around the foliage, which helps prevent disease.
Planting Depth
If you are planting dormant rhizomes, dig a hole about 4 inches deep. Place the rhizome in the hole with the eyes facing up and cover it with soil. If you are transplanting a plant started in a pot, plant it at the same depth it was growing in the container.
Watering and Settling
Water the area deeply immediately after planting. This helps eliminate air pockets around the roots and signals to the plant that it is time to grow. If you are planting in a group, a layer of mulch around the base of the plants will help keep the soil moist and prevent weeds from competing for nutrients.
Summer Care and Maintenance
Once established, canna lilies are relatively low-maintenance, but they do have a few "must-haves" to stay looking their best through the heat of August.
Watering Requirements
Think of cannas as thirsty guests. They prefer consistently moist soil. During the hottest parts of the summer, you may need to water them every few days, especially if they are growing in containers. A deep soaking once or twice a week is better than a light sprinkle every day. This encourages the roots to grow deep into the soil.
Fertilizing for Growth
Because they grow so much foliage in a short time, cannas benefit from regular feeding. You can use a balanced, water-soluble fertilizer every two to four weeks throughout the growing season. Alternatively, you can apply a slow-release granular fertilizer at the time of planting. Look for a formula with a slightly higher middle number (phosphorus) to encourage more blooms.
Mulching Benefits
A 2-inch layer of organic mulch, such as shredded bark or compost, is a gardener’s best friend. It keeps the roots cool, holds in moisture, and slowly improves the soil as it breaks down. Keep the mulch an inch or two away from the actual stems to prevent any moisture-related rot.
Managing the Blooms
Canna flowers are exotic and beautiful, often appearing in clusters at the top of the stems. To keep the show going all summer, a little bit of grooming is helpful.
Deadheading
As the individual flowers in a cluster fade, you can snip them off. This process, called deadheading, keeps the plant looking tidy. Once the entire flower spike has finished blooming and no more buds are visible, cut the whole stalk down to where it meets the next set of leaves. This often encourages the plant to send up a secondary flower stalk.
Staking Tall Varieties
Most cannas have very sturdy stems and do not require staking. However, if you are growing a giant variety in a particularly windy spot, you might find that a sturdy bamboo stake provides some helpful support. Secure the stem to the stake loosely with soft garden twine to allow for growth.
Growing Cannas in Containers
If you don't have a large garden bed, you can still enjoy the tropical beauty of cannas. They are excellent container plants, provided the pot is large enough.
Pot Selection
For a single standard-sized canna, use a container that is at least 15 to 18 inches in diameter. Larger pots are better because they hold more soil and moisture, meaning you won't have to water as often. Make sure the container is heavy enough that it won't tip over when the plant reaches its full height.
Container Soil and Water
Use a high-quality potting mix rather than garden soil. Because pots dry out much faster than the ground, you will need to check the moisture level daily during the summer. If the leaves start to curl or the edges turn brown, it is often a sign that the plant needs more water.
Designing with Containers
Cannas make a perfect "thriller" in the classic thriller-filler-spiller container design. Place the canna in the center or the back of the pot. Surround it with "fillers" like lantana or coleus, and add "spillers" like sweet potato vine to trail over the edges.
Fall Care and Overwintering
When the days grow shorter and the first frost arrives, it is time to think about next year. Whether you need to dig up your rhizomes depends entirely on your climate.
Determining Your Zone
Cannas are tropical perennials. In USDA hardiness zones 7 through 10, they can often stay in the ground year-round. If you want to check shipping timing by zone, Shipping Information includes Longfield Gardens’ hardiness-zone schedule. In these warmer areas, simply cut the foliage back to the ground after it turns brown and apply a thick layer of mulch (6 inches or more) to protect the rhizomes from occasional cold snaps.
Lifting Rhizomes in Cold Climates
In zone 6 and colder, the rhizomes will not survive a frozen winter in the ground. You must "lift" them to save them for next year.
- Wait for Frost: Wait until a light frost has blackened the foliage. This sends a signal to the plant to go dormant.
- Cut Back: Cut the stems down to about 4 inches above the soil.
- Dig Carefully: Use a garden fork or shovel to gently lift the clump of rhizomes. Start digging about a foot away from the stems to avoid cutting into the fleshy roots.
- Clean: Shake off the excess soil. You do not need to wash them perfectly; a little bit of dirt is fine.
- Cure: Let the rhizomes sit in a dry, shaded area (like a garage or shed) for a few days to "cure" or dry out slightly.
Winter Storage
Once cured, place the rhizomes in a cardboard box or a breathable bag. Layer them with slightly damp peat moss, vermiculite, or wood shavings. This keeps them from drying out completely without making them so wet that they rot. Store the box in a cool, dark place where temperatures stay between 40°F and 50°F. A basement or a frost-free crawlspace is usually ideal.
Key Takeaway: Check your stored rhizomes once a month during the winter. If they look shriveled, mist them lightly with water. If you see any soft or rotten spots, remove those pieces immediately to keep the rest of the batch healthy.
Conclusion
Growing canna lilies is one of the easiest ways to bring a sense of adventure and luxury to your home garden. From their impressive height to their vibrant, tropical colors, they offer a massive return on a very small investment of time. Whether you choose to start them early indoors or plant them directly in your sunny borders, these plants are sure to become a favorite part of your summer landscape. At Longfield Gardens, we take pride in providing high-quality rhizomes that help you achieve these stunning results. If you want to learn more about the company behind the plants, visit About Us. With the right mix of sun, water, and rich soil, your garden will be the talk of the neighborhood all season long.
Ready to get started?
- Select a mix of foliage colors for maximum visual interest.
- Prepare your garden beds with plenty of organic compost.
- Plan your watering routine to keep these thirsty plants happy.
- Order your favorite varieties from us to ensure the best selection for the coming season.
FAQ
How long does it take for canna lilies to bloom?
When planted from rhizomes, you can generally expect to see the first flowers in about 10 to 12 weeks. If you give them a head start by planting them indoors 6 to 8 weeks before the last frost, they will often begin blooming much earlier in the summer season.
Do canna lilies come back every year?
In USDA zones 7 through 10, cannas are perennials and will return on their own each spring if the ground does not freeze deeply. In colder zones (6 and below), they are treated as tender perennials, meaning you must dig up the rhizomes and store them indoors over the winter to grow them again the following year.
Can I grow canna lilies in partial shade?
While cannas are famous for their love of full sun, they can tolerate partial shade. However, keep in mind that they will produce fewer flowers, and their foliage colors may not be as intense. If you grow them in shade, they may also grow taller and thinner as they reach for the light, so they might require staking.
Why are the leaves on my canna lily turning brown at the edges?
Brown edges, often called "leaf scorch," are usually a sign that the plant is not getting enough water or that the weather is exceptionally hot and dry. Because cannas have such large leaf surfaces, they lose moisture quickly. Increasing your watering frequency and applying a thick layer of mulch to the soil usually solves this problem.