Introduction
There is a unique sense of accomplishment that comes with a successful summer garden. When your cannas reach their full, tropical height and display those brilliant, fiery blooms, they often become the highlight of the backyard. If you are just getting started, our Tall Cannas collection is a great place to explore the boldest varieties. At Longfield Gardens, we believe that the end of the season is just as exciting as the beginning. It is the time to gather your "garden gold" and tuck it away safely for next year.
If you are new to growing these spectacular plants, you might have some questions as the weather turns cool. One of the most common questions we hear is whether or not you should cut the small, stringy roots off the thick canna rhizomes before putting them away for the winter. Managing these roots is a simple task that makes storage much cleaner and more organized. For a broader look at the plant itself, see our Canna Assorted Collection.
In this guide, we will explain exactly how to handle canna roots, when to do it, and how to ensure your plants return even stronger next spring. This article is for any gardener who wants to save their favorite varieties and enjoy a bigger, better display every year. You can successfully overwinter your cannas by following a few straightforward steps to prepare the rhizomes for their winter nap. If you are comparing standout selections, Canna Tall Tropicanna is one of the most eye-catching choices.
Understanding Canna Anatomy: Rhizomes vs. Roots
Before we address the trimming process, it helps to understand what you are looking at when you dig up a canna. Most gardeners refer to the planting material as "canna bulbs," but they are actually rhizomes. A rhizome is a thick, fleshy horizontal stem that grows underground. It acts as the plant's primary storage organ, holding the energy and nutrients needed to push out new growth in the spring.
The "roots" people often ask about are the thin, mop-like fibers that grow out from the bottom and sides of the thick rhizome. These are feeder roots. During the summer, these roots pull water and minerals from the soil to support the lush leaves and tall flower stalks. Once the plant goes dormant in the fall, these thin feeder roots have finished their job for the year. If you want more growing basics, our Canna Care articles cover the season from planting through storage.
When you lift your cannas, you will see a large, heavy clump consisting of several thick rhizomes intertwined with a dense mass of these hair-like roots. It is important to distinguish between the two. The rhizome is what you want to protect and save. The thin feeder roots are temporary structures that the plant will regrow once it is replanted in warm soil next season.
Should You Cut the Roots Off?
The short answer is yes, you can cut the thin feeder roots off your canna rhizomes before storing them. While it is not strictly mandatory for the plant's survival, most experienced gardeners prefer to trim them. Removing these roots does not hurt the rhizome and offers several practical benefits for the overwintering process.
If you leave the long, mop-like roots attached, they will eventually die back and dry out during storage. This can lead to a messy storage container filled with brittle, dusty root fragments. In some cases, if the storage environment is too damp, these dead roots can hold excess moisture against the rhizome, which may encourage mold. Trimming them away creates a cleaner, more professional-looking "bulb" that is easier to inspect and pack.
At Longfield Gardens, we recommend trimming these roots back so that only about an inch remains, or removing the long, dangling parts entirely. This leaves you with the solid, healthy rhizome and its growth "eyes" (the small bumps where next year’s stems will emerge). A clean rhizome is much easier to wrap in paper or tuck into a bed of peat moss for the winter months. For help matching plants to your climate, our Hardiness Zone Map is a useful planning tool.
The Benefits of Trimming Before Storage
Trimming the roots offers more than just a tidy appearance. It simplifies the entire maintenance process and helps you monitor the health of your plants. Here are the primary reasons why taking a few minutes to trim is a great idea:
- Space Saving: Canna clumps can become quite large after a productive summer. Removing the excess root mass allows you to fit more rhizomes into your storage crates or boxes.
- Disease Prevention: Dead plant material is often where fungal issues or rot begin. By removing the old roots, you reduce the amount of organic "debris" in your storage container that could trap moisture.
- Easy Inspection: When the roots are trimmed, you can clearly see the surface of the rhizome. This makes it easy to spot any soft spots, holes, or signs of pests that need to be addressed before the plant goes into storage.
- Cleaner Handling: Dry, brittle roots can be dusty and messy. Handling cleaned rhizomes in the spring is a much more pleasant experience when you are ready to start potting them up.
Key Takeaway: Trimming the thin feeder roots is a helpful step that makes cannas easier to store, cleaner to handle, and less prone to surface mold.
When is the Right Time to Lift Your Cannas?
Timing is everything when it comes to overwintering tender perennials. You want to give your cannas as much time as possible to store energy in their rhizomes. This energy storage happens primarily in late summer and early autumn.
Wait for the first frost to hit your area. A light frost will usually turn the top leaves black or brown, signaling to the plant that it is time to go dormant. Do not worry if the foliage looks a bit sad after a frost; the thick rhizomes underground are perfectly safe as long as the soil has not frozen solid.
Once the foliage has been "zapped" by the frost, you can cut the stalks down to about three or four inches above the soil line. Leaving a small stub of the stalk gives you a convenient "handle" to hold onto while you dig. It also helps you keep track of which end is up. After cutting the stalks, you can begin the lifting process. If you are still deciding when your season should end, our Shipping Information page shows how Longfield Gardens times shipments by hardiness zone.
How to Safely Dig Canna Clumps
Digging cannas is a rewarding task because you often find that the single rhizome you planted in the spring has multiplied into a large, heavy clump. To keep the rhizomes healthy, you want to avoid nicking or cutting into the fleshy parts with your tools.
A garden fork is often better than a shovel for this job. The tines of a fork can slide between the rhizomes more easily than a solid shovel blade. Start digging about a foot away from the center of the stalk to ensure you stay clear of the main clump. Gently pry upward from several sides until the entire mass of rhizomes and roots lifts out of the ground.
Once the clump is out, give it a gentle shake to remove the heaviest garden soil. You do not need to scrub them perfectly clean at this stage, but removing the bulk of the dirt makes them lighter and easier to move to your workspace.
Cleaning and Curing: The Key to Long-Term Success
Before you reach for your garden snips to trim those roots, the rhizomes need a short period to "cure." Curing is a process of letting the outer skin of the rhizome dry and toughen up slightly. This helps protect the plant from drying out too much during the winter and creates a barrier against rot.
Place your lifted cannas in a well-ventilated, frost-free area like a garage or a covered porch. Let them sit for several days—usually about three to seven days is sufficient. During this time, the remaining soil will dry out and become much easier to brush off.
After the curing period, you can follow these steps to finish the cleaning process:
- Brush away the dry soil: Use your hands or a soft brush to remove the remaining dirt.
- Trim the stalks: If you left long stalks, you can now trim them down to about one or two inches.
- Cut the feeder roots: Use a clean pair of garden snips or scissors to trim away the long, stringy roots. Aim to leave the thick, fleshy rhizome intact.
- Inspect for health: Look for any rhizomes that feel mushy or look shriveled. Discard any that do not feel firm and heavy.
Dividing Your Cannas During the Trimming Process
The time you spend trimming roots is also the perfect opportunity to divide your cannas. Because cannas grow so vigorously, the clumps can become unmanageable if they aren't divided every year or two. Dividing them gives you more plants to share with friends or to spread to different parts of your yard.
To divide, look for the natural "joints" in the rhizome clump. You can usually snap them apart by hand or use a sharp, clean knife to cut them. Each division should have at least one or two "eyes" (the growing points).
If you make any fresh cuts into the fleshy part of the rhizome while dividing, let those pieces air-dry for an extra day or two before packing them away. This allows the cut surface to "callous" over, which is a vital step in preventing rot during storage. If you enjoy this kind of hands-on plant care, you may also like our How to Master Separating Canna Lily Bulbs for a Lush Garden.
What to do next:
- Wait for a light frost to blacken the foliage.
- Cut stalks to 3 inches and lift the clumps with a garden fork.
- Let the rhizomes air-dry in a protected spot for 3–7 days.
- Trim away the stringy roots and cut stalks back to 1 inch.
- Divide large clumps into smaller sections with at least one "eye" each.
Ideal Storage Conditions and Materials
Once your canna rhizomes are cleaned, trimmed, and cured, they are ready for their winter home. The goal of storage is to keep the rhizomes dormant—meaning they should stay cool, dark, and slightly moist, but never wet.
The ideal temperature for storage is between 45°F and 55°F. A cool basement, a crawl space, or a frost-free cellar usually works best. Avoid areas that might freeze, like an unheated detached garage in a cold climate, as freezing will kill the rhizomes. Also, avoid spots that are too warm, like a furnace room, which will cause the rhizomes to shrivel and dry out.
We suggest using a breathable container such as a cardboard box, a plastic bin with air holes, or a wooden crate. To keep the rhizomes from drying out completely, pack them in a moisture-retaining medium. Good options include:
- Peat moss: This is the most common choice and provides excellent insulation.
- Vermiculite or Perlite: These are clean and help regulate moisture levels.
- Wood shavings: Pine or cedar shavings (like the kind used for pet bedding) work very well.
- Newspaper: You can wrap individual rhizomes in several layers of dry newspaper.
Layer the medium in the bottom of the box, place the rhizomes so they are not touching each other, and cover them with more of the material. This "nesting" protects them from temperature fluctuations and prevents any potential rot from spreading from one plant to another.
Monitoring Through Winter
Overwintering is not a "set it and forget it" task. To ensure the best results, we recommend checking on your stored cannas once a month. This small effort can save your entire collection if conditions change.
When you check them, feel a few of the rhizomes. If they feel extremely light or look shriveled, the storage medium might be too dry. In this case, use a spray bottle to lightly mist the packing material with water. You want it to be barely damp, like a wrung-out sponge, not wet.
If you notice any soft or mushy spots on a rhizome, remove that specific piece immediately. This prevents any decay from spreading to the healthy plants. If the packing material feels damp or smells musty, you may need to add some fresh, dry material and improve the ventilation in your storage area.
Gardening with Confidence
Saving your own canna rhizomes is one of the most rewarding ways to grow your garden year after year. By taking the simple step of trimming off the old feeder roots, you set yourself up for a much easier and more successful storage season. These small acts of care ensure that when the spring sun finally warms the soil, your cannas will be ready to burst back into life.
At Longfield Gardens, we want every part of your gardening journey to be enjoyable. Whether you are planting new varieties or preserving your favorites from last summer, the process should feel like a natural part of the season’s rhythm. With your cannas tucked away safely, you can spend the winter planning all the new ways to feature their tropical beauty in your landscape. For more planting and care guidance, explore our Learn section.
Trimming canna roots is a quick task that leads to cleaner storage and healthier plants. Once you see how easy it is to save these beautiful flowers, you will want to do it every year.
We are here to support you with quality plants and practical advice. For more tips on caring for your favorite summer blooms, visit our website to explore our library of guides and planning tools. You can also review our Canna Care resources for related articles.
FAQ
Is it okay to leave the roots on my cannas if I’m in a hurry?
Yes, you can leave the roots on if necessary, and it will not kill the plant. However, the roots will eventually dry out and become brittle, making the storage container messier and harder to manage when spring arrives. Trimming them is simply a "best practice" for easier handling.
How do I know the difference between a healthy rhizome and a dead one?
A healthy canna rhizome should feel firm and heavy, similar to a fresh ginger root or a potato. If a rhizome feels light, hollow, or "squishy" when you press on it, it has likely either dried out or succumbed to rot and should be discarded.
Should I wash the rhizomes with a hose before trimming the roots?
It is generally better to avoid washing cannas with a hose unless your soil is extremely heavy clay that won't come off any other way. Excess water can get trapped in the nooks and crannies of the rhizome, increasing the risk of rot during storage. Letting them air-dry and then brushing off the soil is the safer method. If you need help with fall shipping timing, check our Shipping Information page.
Do I need to use a fungicide on the rhizomes after trimming?
For most home gardeners, a fungicide is not necessary if the rhizomes are properly cured and stored in the right conditions. The most important "fungicide" is simply ensuring the rhizomes are dry to the touch and that the storage medium is not overly wet. If you have had rot issues in the past, you can lightly dust the cut ends with sulfur powder.
Can I keep cannas in the ground where winters are mild?
In warmer regions, some gardeners do leave cannas in the ground. If you want to compare your garden conditions with the plant's needs, our Hardiness Zone Map can help you decide whether lifting is necessary.
