Table of Contents
- Introduction
- Understanding Canna Rhizomes
- The Benefits of Dividing Your Cannas
- Choosing the Right Time to Split
- Essential Tools for the Job
- Step-by-Step: How to Split Canna Lily Bulbs
- Curing and Storing Divisions
- Planting Your New Canna Divisions
- Best Growing Practices for Healthy Cannas
- Conclusion
- FAQ
Introduction
There is nothing quite like the tropical flair that canna lilies bring to a summer garden. Cannas are beloved for their massive, paddle-shaped leaves and vibrant, exotic blooms that last until the first frost. If you have grown these beauties before, you know how quickly they can transform a backyard into a lush paradise. At Longfield Gardens, we enjoy seeing how a single season of growth can turn a small planting into a magnificent, multi-stemmed display. For more canna care resources, see Canna Planting & Care.
Because cannas are such vigorous growers, they naturally outgrow their space over time. Learning how to split canna lily bulbs is one of the most rewarding skills a gardener can develop. It is a simple, cost-effective way to multiply your favorite varieties and keep your plants healthy and blooming year after year. This guide will walk you through the entire process, from choosing the right time to making the perfect cut.
Splitting cannas is a straightforward task that any gardener can master with a little bit of patience and a sharp tool. By following a few basic steps, you can double or even triple your collection of these stunning tropical plants.
Understanding Canna Rhizomes
Before you start digging, it is helpful to understand what you are actually handling. While most people refer to them as bulbs, canna lily bulbs actually grow from rhizomes. A rhizome is a thick, fleshy underground stem that grows horizontally just beneath the soil surface. This stem stores energy and water, which allows the plant to produce those tall, impressive stalks and large leaves.
Rhizomes are different from true bulbs, like tulips or daffodils, which are more like underground buds with layers. Because a rhizome grows outward, it naturally creates new growth points as it moves through the soil. These growth points are often called "eyes." They look like small, swollen bumps or pointed tips on the surface of the fleshy root. Each of these eyes has the potential to become a brand-new plant.
When we talk about splitting canna lily bulbs, we are actually talking about cutting these rhizomes into smaller pieces. As long as each piece has at least one healthy eye, it can grow into a full-sized canna lily. This unique growth habit makes cannas one of the easiest plants in the garden to propagate.
The Benefits of Dividing Your Cannas
Dividing your plants is not just about getting more flowers for free, though that is a wonderful perk. It is also an essential part of maintaining a healthy and beautiful garden. When cannas are left to grow in the same spot for many years without intervention, they can become overcrowded.
Overcrowded plants have to compete for the same nutrients, water, and sunlight. This competition can lead to smaller leaves and fewer flowers. In some cases, the center of an old clump may even stop producing new growth altogether. By splitting the rhizomes, you give the plants more room to breathe and access the resources they need.
Another benefit of splitting is the ability to share your garden with others. Cannas like ‘Pretoria’ or 'Wyoming' are always popular with neighbors and friends. Having extra divisions means you can easily pot them up as gifts or trade them for other plant varieties. It is a great way to build a community of fellow gardening enthusiasts.
Key Takeaway: Dividing cannas prevents overcrowding, encourages larger blooms, and provides you with extra plants to expand your garden or share with friends.
Choosing the Right Time to Split
Timing is everything when it comes to splitting canna lily bulbs. While these plants are quite resilient, you want to perform the division when the rhizomes are most likely to recover quickly and start new growth. There are two primary windows of time for this project: spring and fall.
Spring Division
Most gardeners prefer to split their cannas in the spring. This is the ideal time because the plants are just waking up from their winter dormancy. As the soil warms, the eyes on the rhizomes will begin to swell and may even start to show small green tips. This makes it very easy to see exactly where to make your cuts.
If you live in a region with cold winters, you likely dug up your canna rhizomes in the fall and stored them in a cool, dry place. In the spring, about four to six weeks before the last frost, you can take them out of storage to divide them. This timing allows you to pot up the new divisions and get them started indoors before moving them out to the garden.
Fall Division
If you live in a warm climate (USDA zones 8 or higher) where cannas can stay in the ground all year, you can divide them in the late fall or early winter. If you are not sure of your zone, check the Hardiness Zone Map. In these areas, the plants may need to be split every three to four years to keep them from taking over their garden beds.
For gardeners in colder zones, you can also split your rhizomes in the fall right after you dig them up for storage. The advantage here is that the rhizomes are already out of the ground, and you can clean them and split them before tucking them away for the winter. However, it can sometimes be harder to see the eyes in the fall than it is in the spring.
Essential Tools for the Job
You do not need a lot of fancy equipment to split canna lilies. In fact, you likely already have everything you need in your garden shed. Having the right tools clean and ready will make the process go much faster and keep your plants healthy.
- A sturdy garden fork or shovel: You will need this to lift the large clumps out of the ground. A garden fork is often better because it is less likely to accidentally slice through the rhizomes.
- A sharp, clean knife: A simple serrated garden knife or a large kitchen knife works well. It is important that the blade is sharp so you can make clean cuts.
- A garden hose: You will want to wash the soil off the rhizomes so you can see the eyes clearly.
- Gloves: Canna rhizomes can be muddy, and some people find the sap a bit sticky.
- Optional: Rubbing alcohol or a bleach solution: Use this to disinfect your knife between cuts to prevent the spread of any soil-borne issues.
Step-by-Step: How to Split Canna Lily Bulbs
Once you have your tools ready and the timing is right, it is time to get to work. Follow these simple steps to ensure your canna divisions are successful and ready to grow.
Step 1: Lift the Clump
If your cannas are in the ground, start by cutting the foliage back to about three or four inches above the soil line. Use your shovel or garden fork to dig a wide circle around the base of the plant. Canna rhizomes can spread quite far, so give them plenty of space. Gently pry the clump upward from several sides until it pops loose from the soil.
If your cannas are in containers, simply tip the pot over and slide the root ball out. You may need to tap the sides of the pot to loosen the soil.
Step 2: Clean the Rhizomes
It is very difficult to see what you are doing when the rhizomes are covered in dirt. Use a garden hose to wash away as much soil as possible. If the soil is heavy clay, you might need to use your hands to gently work the mud out from between the sections. Once the rhizomes are clean, you will be able to see the individual segments and the small, pointed eyes.
Step 3: Identify the Eyes
Look closely at the surface of the rhizome. You are looking for small bumps that look like the eyes on a potato. These are the growth points. For a successful division, every piece you cut must have at least one healthy eye. However, we recommend aiming for two or three eyes per piece. This ensures the new plant has plenty of energy to produce a strong stalk quickly.
Step 4: Make the Cuts
Use your sharp knife to cut the rhizome into sections. Look for the natural "joints" where the rhizome has branched out. These are the best places to make your cuts. Try to make the cuts as clean and straight as possible. A clean surface heals faster than a jagged one.
If you encounter a very large, old section of rhizome that has no eyes and feels soft or hollow, you can simply cut it away and discard it. You want to keep the firm, light-colored, healthy sections.
Step 5: Inspect Your Divisions
After you have finished cutting, look over each piece. A healthy canna division should feel firm to the touch, similar to a fresh potato. If you find any pieces that feel mushy or look shriveled, it is best to toss them out. It is much better to start with five healthy divisions than ten weak ones.
What to do next:
- Gather your tools and find a flat, comfortable workspace.
- Carefully lift the canna clump and wash away all the soil.
- Locate the eyes and plan your cuts to include 2-3 eyes per piece.
- Make clean, decisive cuts with a sharp knife.
Curing and Storing Divisions
One of the most important steps in splitting canna lily bulbs is allowing the cuts to "cure" or callus over. When you cut a rhizome, you are creating an open wound. If you plant that freshly cut piece directly into wet soil, it may be susceptible to rot before it has a chance to grow. For step-by-step winter storage, see How to Divide and Store Canna Bulbs for Winter.
To cure your divisions, place them in a dry, shaded area for 24 to 48 hours. A garage, shed, or a spot on your porch works perfectly. During this time, the cut surface will dry out and form a tough, skin-like layer. This natural "scab" protects the rhizome from soil organisms and helps keep the moisture inside the plant.
If you are splitting your cannas in the fall for winter storage, you can cure them for a few days and then pack them away. We recommend placing the dry rhizomes in a cardboard box or a plastic bin with some slightly damp peat moss or vermiculite. Store them in a cool, dark place that stays between 40°F and 50°F. Check on them once or twice during the winter to make sure they aren't getting too dry or too wet.
Planting Your New Canna Divisions
When the weather is right and your divisions are cured, it is time to get them back into the dirt. Planting cannas is a simple process, but getting the depth and spacing right will set them up for a fantastic season.
Choosing the Location
Cannas are sun-loving plants. For the best flowers and the brightest foliage, choose a spot that gets at least six hours of direct sunlight every day. They also appreciate soil that holds some moisture but drains well. "Drainage" simply refers to how fast water leaves the soil. If water sits in a puddle for hours after a rain, the spot might be too wet for cannas.
Planting Depth and Spacing
Dig a hole or a trench that is about four inches deep. Place the rhizome in the hole horizontally, with the eyes facing upward. If you aren't sure which way is up, don't worry—the plant will figure it out! Space your divisions about one to two feet apart. While they look small now, Tropicanna grows quite large and will need that space by mid-summer.
The First Watering
After you cover the rhizomes with soil, give them a good drink of water. This helps settle the soil around the roots and signals to the plant that it is time to start growing. If you are planting in the spring, be patient. Cannas love heat, so they may not show much growth above ground until the soil temperatures stay consistently warm.
Best Growing Practices for Healthy Cannas
Once your divisions are in the ground, a little bit of ongoing care will ensure they reach their full potential. At Longfield Gardens, we believe that consistent care is more important than complicated tricks.
- Watering: Cannas have large leaves that lose water quickly in the heat. During the peak of summer, they appreciate regular watering. The goal is to keep the soil consistently moist but not soggy. If you are growing them in containers, see How to Plant Canna Bulbs in a Pot.
- Fertilizing: Because they grow so fast, cannas are heavy feeders. They appreciate a boost of nutrients every few back weeks during the growing season. A balanced, all-purpose fertilizer works well. Follow the instructions on the label for the best results.
- Deadheading: To keep the flowers coming, remove the faded blooms. Cut the flower stalk back to the next side bud or leaf. This prevents the plant from putting energy into making seeds and encourages it to produce more flowers instead.
- Mulching: Adding a layer of mulch around the base of the plants helps retain moisture in the soil and keeps the roots cool. It also helps suppress weeds that might compete with your cannas.
"A small investment of time in the spring leads to a massive payoff of tropical color in the summer. Dividing cannas is the secret to a garden that looks better every single year."
Conclusion
Splitting canna lily bulbs is one of the easiest and most effective ways to enhance your summer garden. By taking a large, crowded clump and turning it into several healthy new plants, you ensure that your cannas stay vigorous and produce the best possible show of flowers and foliage. Whether you are expanding your own beds or sharing plants with a friend, the process is simple, rewarding, and full of potential.
We hope this guide gives you the confidence to head out into the garden and start multiplying your tropical favorites. Remember that gardening is a journey, and each task is an opportunity to learn more about how your plants grow. At Longfield Gardens, we are here to support you with high-quality plants and the practical advice you need to succeed.
- Wait for the right time in spring or fall to divide.
- Use clean, sharp tools for the healthiest cuts.
- Ensure every division has at least one to three healthy eyes.
- Allow the rhizomes to cure before planting or storing.
We invite you to explore our selection of cannas and other spring-planted summer-blooming bulbs to find the perfect additions to your outdoor space. Happy planting!
FAQ
How many eyes should each canna division have?
For the best results, aim for two to three eyes per division. While a piece with only one eye can grow into a plant, having multiple eyes ensures a fuller, more vigorous plant in its first season. Each eye will eventually become a new stalk, so more eyes generally lead to a faster-established clump. For a step-by-step refresher, see How Do You Separate Canna Bulbs for More Flowers?.
What happens if I don't split my canna lilies?
If you don't split them, the clump will eventually become overcrowded. This can lead to smaller flowers, shorter stems, and less vibrant foliage as the plants compete for nutrients. Over time, the center of the clump may even die out, leaving you with a ring of growth instead of a full, lush plant.
Can I split cannas while they are still growing in the summer?
While it is possible, it is not recommended because it causes a lot of stress to the plant during its peak growing and blooming phase. Splitting in the summer often results in wilted leaves and a loss of flowers for the rest of the season. It is much better to wait until the plant is dormant or just waking up in the spring.
Do I need to use a special powder on the cut ends of the rhizomes?
Some gardeners like to dust the cut ends with sulfur powder or cinnamon to prevent rot, but it is not strictly necessary. The most important step is to allow the rhizomes to "cure" in a dry place for 24 to 48 hours. This allows the plant to form its own natural protective callus, which is usually enough to keep it healthy.