Table of Contents
- Introduction
- Understanding Canna Lily Rhizomes
- Why You Should Separate Canna Lilies
- The Best Time to Separate Canna Lily Bulbs
- Tools You Will Need
- How to Separate Canna Lily Bulbs: Step-by-Step
- Identifying Healthy Sections
- Caring for Your New Canna Divisions
- Lifting and Storing Separated Cannas
- Popular Canna Varieties to Divide
- Realistic Expectations for Your Divisions
- Troubleshooting Common Division Issues
- Conclusion
- FAQ
Introduction
Watching the bold, tropical foliage of a canna lily unfurl in the summer sun is one of the most rewarding moments in the garden. These canna lilies grow with incredible speed and energy, often transforming from a small tuber into a towering focal point in just a few months. Because they are such vigorous growers, they eventually need a little extra room to keep performing their best.
At Longfield Gardens, we enjoy seeing how a single season of growth can turn one plant into a large, healthy clump. To start with a mixed selection, try our Canna Assorted Mix - Bulk Offer. Learning how to separate these plants is a simple skill that every gardener can master. It allows you to refresh the health of your original plants while gaining plenty of new ones to share with friends or tuck into other parts of your landscape.
This guide will walk you through the straightforward process of dividing your cannas to ensure they stay vibrant and bloom reliably year after year. Whether you are lifting them for winter storage or thinning out a crowded garden bed, the steps are easy to follow and highly effective. Splitting your cannas is the best way to maintain a lush, tropical garden without extra cost.
Understanding Canna Lily Rhizomes
Before you start digging, it helps to understand what you are actually looking at beneath the soil. While many people refer to them as "bulbs," cannas actually grow from rhizomes. For a broader overview, read All About Cannas. A rhizome is a thick, fleshy underground stem that grows horizontally just below the soil surface.
Think of a rhizome as a storage tank for the plant. It holds the energy and nutrients the canna lily needs to push out those massive leaves and bright flowers. As the plant grows throughout the summer, the rhizome expands and creates new "eyes" or growth points. Each of these eyes has the potential to become a brand-new plant.
When a canna clump gets too large, the rhizomes can become tangled and crowded. This leads to smaller flowers and thinner stems because the plants are competing for the same nutrients. Separating them every few years keeps the energy focused and gives each new shoot the space it needs to thrive.
Why You Should Separate Canna Lilies
Separating your cannas is not just about getting more plants for free, though that is a wonderful benefit. It is also an essential part of plant maintenance. Like many perennials, cannas eventually exhaust the soil around them and become physically crowded. For more growing inspiration, see Fresh Ideas for Growing Cannas.
When you divide the rhizomes, you are essentially hitting a "reset" button for the plant. You remove the older, less productive parts of the root system and give the young, vigorous sections a fresh start. This results in larger leaves, more intense colors, and a longer blooming season.
It also gives you a chance to inspect the health of your plants. While you are separating them, you can easily spot any sections that look soft or tired and set them aside. This ensures that only the strongest, healthiest material goes back into your garden or into storage for the winter.
Key Takeaway Dividing cannas prevents overcrowding and revitalizes the plant. It ensures you have the strongest growth and the most vibrant blooms for the following season.
The Best Time to Separate Canna Lily Bulbs
Timing is one of the most important factors when it comes to successfully separating your cannas. While these plants are hardy and resilient, they respond best when divided during specific windows in the growing cycle.
Spring Division
For most gardeners, spring is the ideal time to separate canna lily rhizomes. This is usually done just as the plants are waking up from dormancy but before they have put significant energy into tall stems. In warmer climates where cannas stay in the ground year-round, you can divide them in late winter or early spring before new growth starts.
If you live in a cooler region and have stored your rhizomes indoors for the winter, spring is the perfect time to check them over. You can separate them right before you pot them up or plant them in the ground. This allows the new divisions to establish roots immediately in the warming soil.
Fall Division
In northern zones where the ground freezes, cannas must be lifted and stored indoors. The Hardiness Zone Map can help you check your area before you decide when to lift them.
If you divide in the fall, it is important to let the cut ends "cure" or dry out for a few days before putting them into storage. This helps prevent moisture from causing issues during the winter months. Regardless of when you choose to do it, the physical process of separating the rhizomes remains the same.
Tools You Will Need
You do not need an extensive kit of specialized tools to separate canna lilies. In fact, you likely already have everything you need in your garden shed. The most important thing is to make sure your tools are clean and sharp.
- A garden fork or spade: These are used to lift the entire clump out of the ground. A fork is often better because it is less likely to accidentally slice through the rhizomes.
- A sharp gardening knife: A clean, sharp blade makes precise cuts, which helps the plant heal faster. A serrated knife can also work well for very large, woody clumps.
- A garden hose: This is used to wash away soil so you can clearly see the rhizomes and the growth "eyes."
- Gloves: Cannas are not typically irritating, but gardening is always more comfortable with a good pair of gloves.
- A workspace: A potting bench, a tarp on the grass, or even a driveway works well for laying out the rhizomes.
Using clean tools is a simple way to keep your plants healthy. Before you start, we recommend wiping your knife blades with a bit of rubbing alcohol or a mild soap solution. This ensures that no unwanted organisms are moved from one plant to another.
How to Separate Canna Lily Bulbs: Step-by-Step
Once you have your tools ready and the timing is right, the process of separating cannas is straightforward. Following these steps will help you get the best results with minimal stress on the plants.
Step 1: Lift the Clump
Start by digging around the perimeter of the canna clump. Cannas have relatively shallow but wide-reaching root systems. Aim your spade or fork about six to eight inches away from the outermost stems. Gently pry upward from several sides to loosen the soil and lift the entire mass of rhizomes out of the earth.
Step 2: Clean the Rhizomes
It can be difficult to see where to cut when the rhizomes are covered in dirt. Use your garden hose to spray off the excess soil. You do not need to make them perfectly clean, but you want to see the individual "fingers" of the rhizomes and the small, pointed buds known as eyes.
Step 3: Identify the Eyes
Before you make any cuts, look for the eyes. These look like small, rounded or pointed bumps on the surface of the fleshy rhizome. They are often pink, white, or light green. For a division to be successful, each piece must have at least one healthy eye, though two or three eyes per section will produce a fuller plant much faster.
Step 4: Make the Cuts
Using your sharp knife, cut the rhizomes into sections. Try to make clean, vertical cuts. Each section should be about three to five inches long and contain those vital eyes. If the clump is very old, you might find a "mother" rhizome in the center that looks shriveled or has no eyes; you can simply cut this away and compost it.
Step 5: Inspect and Trim
Take a moment to look at each new division. If you see any long, dangling roots, you can trim them back slightly to make planting easier. If any part of a rhizome feels soft or mushy, trim that section off until you reach firm, white flesh.
Step 6: Let Them Cure
If you are planting the divisions immediately in the spring, you can put them straight into the soil. However, if you are dividing them in the fall for storage, or if the soil is very wet, let the pieces sit in a dry, shaded spot for 24 to 48 hours. This allows the cut surfaces to callous over, which acts as a natural seal.
What to do next
- Clear a flat workspace where you can see all your divisions.
- Wash away enough soil to see the pink or white "eyes."
- Ensure every piece you keep has at least one strong growth point.
- Discard any pieces that feel soft or look shriveled.
- Allow cut ends to dry for a day if you aren't planting them right away.
Identifying Healthy Sections
The success of your newly separated cannas depends entirely on the quality of the sections you choose to keep. Not every piece of a large clump needs to be saved. In fact, being a bit selective will lead to a much more beautiful garden.
A healthy canna division should feel heavy for its size, almost like a fresh potato. It should be firm to the touch, not rubbery or soft. The skin should be relatively smooth, though it is normal for it to have some papery scales or leftover root hairs.
The most important feature is the "eye." This is the point where next year's leaves and flowers will emerge. A healthy eye is firm and often has a slightly different color than the rest of the rhizome. If a section of rhizome is large and healthy but has no visible eyes, it is unlikely to grow. Always prioritize the pieces that show active growth points.
Caring for Your New Canna Divisions
After you have successfully separated your canna lily bulbs, they need a little care to help them get established in their new homes. Their needs will change slightly depending on whether you are planting them in the garden or starting them in pots.
Planting in the Garden
Wait until the danger of frost has passed and the soil has warmed to at least 60°F. Cannas love heat and will sit idle in cold, wet soil. Plant the rhizomes about 2 to 3 inches deep. If you are planting several divisions, space them about 1 to 2 feet apart to give them room to grow into large clumps again.
Position the rhizome horizontally in the planting hole with the eyes facing upward. Cover with soil and water them well to settle the earth around the roots. You do not need to water constantly at first; just keep the soil lightly moist until you see the first green shoots poking through the ground.
Starting in Containers
If you want a head start on the season, you can plant your new divisions in pots indoors or in a greenhouse about 4 to 6 weeks before the last frost. Use a well-draining potting mix and keep the containers in a warm, bright spot. This gives the plants time to develop a strong root system so they are ready to take off the moment they are moved outside.
Water and Fertilizer
Once cannas start growing, they are hungry and thirsty plants. They thrive with regular deep watering, especially during the heat of mid-summer. We recommend using a balanced, slow-release fertilizer or adding a bit of compost to the planting hole to give them the nutrients they need for those large leaves and bright blooms.
Lifting and Storing Separated Cannas
In USDA hardiness zones 7 and colder, cannas are usually treated as annuals or lifted and stored for the winter. For a fuller look at winter care, see How to Overwinter Canna Lily Bulbs. If you have just separated your cannas in the fall, storage is the next vital step. Proper storage ensures that your hard work in dividing them pays off when spring arrives.
After the first light frost has blackened the foliage, cut the stems down to about 2 or 3 inches above the ground. Carefully lift the clumps and separate them as described above. Once the cut ends have cured for a couple of days, it is time to pack them away.
Place the divisions in a sturdy box or plastic bin. We find that layering them with slightly damp peat moss, sawdust, or vermiculite works best. This keeps the rhizomes from drying out completely without making them so wet that they rot. Store the container in a cool, dark place that stays between 40°F and 50°F, such as a basement or crawl space.
Check on your stored divisions once or twice during the winter. If the packing material feels bone-dry, give it a very light misting of water. If you see any signs of softness, remove those pieces immediately to keep the rest of the batch healthy.
Popular Canna Varieties to Divide
At Longfield Gardens, we offer a variety of cannas that are known for their vigor and ease of division. For taller selections, browse our Tall Cannas collection. Different varieties have different growth habits, which can affect how often they need to be separated.
- Tropicanna: Known for its spectacular striped foliage in shades of bronze, gold, and pink. It is a vigorous grower that produces plenty of new rhizomes each season.
- Wyoming: This variety features dark, bronze-purple leaves and bright orange flowers. It grows quite tall and benefits greatly from being thinned out every few years.
- Pretoria (Striata): A classic favorite with yellow and green striped leaves. It creates very dense clumps that are easy to see and separate once lifted.
- Dwarf Varieties: If you grow shorter cannas in containers, you will notice they fill their pots very quickly. Separating these every spring is essential to keep them from becoming root-bound.
No matter which variety you choose, the principles of separation remain the same. The goal is always to provide the plant with fresh soil and enough space to reach its full potential.
Realistic Expectations for Your Divisions
When you separate canna lily bulbs, it is helpful to keep a few things in mind regarding their first season of growth. While cannas are fast growers, a small division with only one eye will naturally take a little longer to become a massive clump than a larger piece with three or four eyes.
During the first few weeks after planting, you might not see much action above ground. The plant is busy established a new root system from the cut rhizome. This is perfectly normal. Once the roots are set, the top growth will usually appear quite suddenly and grow rapidly.
Weather also plays a huge role. If you have a particularly cool or cloudy summer, your cannas may grow a bit slower or produce fewer flowers. On the other hand, in hot and sunny weather, you might find that your new divisions grow so fast you will need to separate them again in just a couple of years! Gardening is a partnership with nature, and being patient during the early stages of growth is always worth it.
Troubleshooting Common Division Issues
Separating cannas is usually a very successful project, but occasionally things don't go exactly as planned. Most issues are easy to fix with a few simple adjustments.
If your new divisions aren't sprouting, the most likely cause is soil temperature. As we mentioned, cannas love heat. If the ground is still cold, the rhizome will simply stay dormant. You can often "wake them up" by placing a clear plastic cover or a cloche over the planting area to help trap solar heat.
If you notice the leaves are looking a bit pale or the plant isn't growing as fast as you expected, it might need more nutrients. Cannas are "heavy feeders," meaning they use up a lot of nitrogen and potassium to build those big stems. A quick application of a liquid fertilizer can often provide the boost they need to get back on track.
If a division feels soft after planting, it may have been overwatered before it had enough roots to process the moisture. In this case, it is best to let the soil dry out significantly before watering again. For the best results, always start with firm, healthy rhizomes and wait for active growth before you begin a heavy watering schedule.
Conclusion
Separating canna lily bulbs is one of the easiest ways to expand your garden and maintain the health of your plants. By taking the time to lift, clean, and cut your rhizomes every few years, you ensure that your landscape remains filled with the vibrant, tropical beauty that only cannas can provide. It is a simple, satisfying task that connects you more deeply with the lifecycle of your garden.
At Longfield Gardens, we want to help you feel confident in every gardening project you undertake. Remember that these plants are incredibly resilient and eager to grow. Whether you are a beginner or a seasoned gardener, dividing your cannas is a practical step that leads to a more beautiful and productive yard.
- Wait for the right time: Divide in spring for immediate growth or fall for easier storage.
- Look for the eyes: Ensure every new piece has at least one healthy growth point.
- Clean and cure: Use sharp tools and let the cut ends dry if you aren't planting right away.
- Provide heat and water: Give your new divisions plenty of sun and regular moisture once they start growing.
Separating your cannas is an investment in the future of your garden. With just a little bit of effort, you can turn a single beautiful plant into a stunning tropical border.
If you are ready to add new colors or textures to your collection, we invite you to explore our selection of premium canna rhizomes. We stand behind our quality with a 100% guarantee, ensuring your plants arrive ready to thrive in your garden. Happy planting!
FAQ
How many eyes should each canna division have?
Each division should have at least one healthy growth eye, which is a small, firm bud on the surface of the rhizome. However, we recommend keeping two or three eyes per section if possible. This allows the plant to produce multiple stems more quickly, resulting in a fuller, more impressive display in its first season.
Do I need to treat the cut ends of the rhizome with anything?
While some gardeners use sulfur powder to prevent rot, it is generally not necessary if you let the rhizomes "cure." Simply leaving the cut pieces in a dry, shaded area for 24 to 48 hours allows the surface to callous over naturally. This callous acts as a protective barrier against soil-borne issues.
Can I separate cannas while they are still blooming?
It is best to avoid separating cannas while they are in full bloom, as this causes significant stress to the plant and will likely end the flowering season prematurely. If you must move them during the summer, try to take as much of the original soil as possible and wait until the plant has finished its main flowering flush before attempting to divide the rhizomes.
Why are my divided cannas not growing leaves yet?
The most common reason for slow growth is cold soil. Canna lilies are tropical plants that require soil temperatures of at least 60°F to begin active growth. If you planted them early in the spring, they may simply be waiting for the weather to warm up; once the heat arrives, they will usually grow very rapidly.