Should I Cut the Roots Off Canna Bulbs Before Storing?

Introduction
Understanding Canna Rhizomes and Roots
Should You Cut the Roots Before Storing?
When to Dig Your Cannas
Step-by-Step: How to Lift and Clean Canna Rhizomes
The Importance of Curing
How to Handle the Roots During Curing
Dividing Canna Rhizomes
Packing Your Cannas for Winter
Finding the Best Storage Location
Monitoring Your Rhizomes Through Winter
Bringing Cannas Out of Storage
Summary of the Canna Storage Cycle
Conclusion
FAQ

Introduction

Canna lilies are the champions of the summer garden. Their bold foliage and vibrant flowers bring a tropical energy to any yard, often reaching impressive heights in just one season. If you live in a region with cold winters, the fun doesn't have to end when the first frost arrives. Saving these plants for next year is a rewarding way to build your garden collection while keeping your favorite colors year after year.

At Longfield Gardens, we want to help you feel confident as you tuck your plants away for their winter nap. One of the most common questions gardeners ask during this process is what to do with the "hairy" roots attached to the main bulb. This guide is designed for home gardeners who want clear, practical steps for cleaning and storing cannas so they return even stronger in the spring.

By following a few simple steps to prepare your plants, you can ensure your canna rhizomes stay healthy and hydrated until it is time to plant again. Knowing how to handle the roots and the curing process is the key to overwintering success.

Understanding Canna Rhizomes and Roots

Before you pick up your garden shears, it helps to know what you are looking at. While many people call them "bulbs," cannas actually grow from rhizomes. A rhizome is a thick, fleshy underground stem that stores energy and nutrients for the plant.

When you lift a canna clump out of the ground in the fall, you will see two distinct parts. There is the thick, firm rhizome itself, and then there are the many thin, stringy "feeder" roots growing out of it. These smaller roots are responsible for pulling water and nutrients from the soil during the summer.

Once the plant goes dormant for the winter, these thin roots are no longer active. They have finished their job for the season. The rhizome is the part that contains the "eyes" or growth points that will produce next year’s stalks. Because the rhizome is the powerhouse of the plant, that is the part we focus on protecting during storage.

Should You Cut the Roots Before Storing?

The short answer is yes, you can safely cut the thin, stringy roots off your canna bulbs before you store them. In fact, many gardeners prefer to do this because it makes the storage process much cleaner and more organized.

Trimming these roots serves several practical purposes:

Space Saving: Without the mass of tangled roots, the rhizomes take up much less room in your storage boxes.
Cleanliness: Roots often hold onto extra soil and debris. Removing them helps keep your storage medium, such as peat moss or wood shavings, cleaner.
Rot Prevention: In some cases, old roots can hold excess moisture or begin to decay during the winter. Removing them reduces the risk of mold or rot spreading to the healthy rhizome.

While you can trim these roots, you do not need to be aggressive. You are simply giving the rhizome a "haircut" to tidy it up. The plant will grow a completely new set of feeder roots once you replant it in the warm soil next spring.

When to Dig Your Cannas

Timing is everything when it comes to lifting cannas. In most parts of the United States, we recommend waiting until the first frost has touched the foliage. You will notice the leaves turn black or brown after a cold night. This is a natural signal to the plant that it is time to move its energy down into the rhizome for dormancy.

Wait a few days after that first frost before you start digging. This brief waiting period allows the plant to finish its transition into a dormant state. However, do not wait so long that the ground begins to freeze solid. A light surface frost is fine, but a deep freeze that reaches the rhizome can cause damage.

If you garden in USDA Hardiness zones 8–10, you may not need to dig your cannas at all. They can often stay in the ground year-round with a bit of mulch for protection. But for those of us in cooler zones, lifting them is a necessary part of the autumn garden routine.

Step-by-Step: How to Lift and Clean Canna Rhizomes

Lifting canna clumps is a straightforward process. Having the right tools and a gentle touch will ensure you don't bruise the fleshy rhizomes.

1. Cut Back the Foliage

Before you reach for your shovel, use a pair of garden shears to cut the stalks down. Leave about 2 to 4 inches of the stem attached to the rhizome. This stub serves as a handy "handle" for moving the rhizome around and helps you remember which side is up when you replant in the spring.

2. Loosen the Soil

Use a garden fork rather than a pointed shovel if possible. A garden fork is less likely to slice through the rhizomes. Start digging about 6 to 10 inches away from the base of the plant. Gently rock the fork back and forth to loosen the soil all the way around the clump.

3. Lift the Clump

Once the soil is loose, gently lift the entire mass out of the ground. Don't be surprised if the clump is much larger than what you planted in the spring. Cannas are vigorous growers and love to multiply over the summer.

4. Remove Excess Soil

Shake the clump gently to knock off large chunks of dirt. You can use your hands to brush away loose soil. Some gardeners like to use a garden hose to rinse the rhizomes clean. This makes it easier to see where to make cuts if you plan to divide them. If you do wash them, just be sure to let them dry thoroughly afterward.

Key Takeaway: Always use a garden fork to lift cannas to minimize the risk of cutting into the fleshy rhizome. Leaving a short stem stub makes handling easier and identifies the top of the plant.

The Importance of Curing

Curing is perhaps the most important step in the entire winter storage process. This is the period where you allow the outer skin of the rhizome to dry and toughen up. Think of it like the skin on an onion; a dry, firm outer layer acts as a natural barrier against rot and disease.

To cure your cannas, find a spot that is out of the direct sun but has good air circulation. A garage, a covered porch, or a shed works well. Spread the rhizomes out in a single layer on a piece of cardboard or a newspaper.

Let them sit for about 3 to 7 days. During this time, any remaining soil will dry out and fall off easily. Most importantly, the "wounds" where you cut the stalks or where the rhizomes may have naturally snapped apart will callow over. A calloused surface is much less likely to develop mold during the winter months.

How to Handle the Roots During Curing

You have two choices for when to trim the roots: right after digging or after the curing process.

Many people find it easiest to trim the roots after curing. When the roots are dry, they become brittle and easier to snip away. You can use a pair of clean scissors or garden snips to remove the long, stringy bits. You don't need to get every single tiny fiber. Just aim for a clean, manageable rhizome that looks similar to the ones you originally bought.

If you notice any soft spots or damaged areas on the rhizome itself during this stage, you can trim those away as well. Use a sharp, clean knife and let the fresh cut air-dry for another day to ensure it callouses over before going into storage.

Dividing Canna Rhizomes

As you clean and trim the roots, you might notice that your canna clumps are quite large. Fall is a great time to divide them, though you can also wait until spring.

To divide them, look for the "eyes"—these are the small, rounded bumps on the rhizome where new growth will emerge. Each piece you save should have at least one or two healthy eyes. You can often simply snap the rhizomes apart at the narrow points where they join, or use a clean knife to make a purposeful cut.

Dividing your cannas every year or two prevents the clumps from becoming too crowded. It also gives you more plants to share with friends or to fill new corners of your garden.

Packing Your Cannas for Winter

Once your rhizomes are cured and the roots are trimmed, it is time to pack your canna rhizomes away. The goal is to keep them in a "goldilocks" state: not so wet that they rot, and not so dry that they shrivel up like a raisin.

Choosing a Storage Medium

We recommend using a material that can hold a tiny bit of moisture while still allowing the rhizomes to breathe. Good options include:

Peat Moss: A classic choice that provides excellent insulation.
Vermiculite: A mineral that helps regulate moisture levels.
Wood Shavings: Often sold as animal bedding, these are inexpensive and effective.
Newspaper: You can wrap each rhizome individually in several layers of dry newspaper.

Selecting a Container

Avoid plastic bins with tight-fitting lids. These trap moisture and are the leading cause of rot. Instead, use:

Cardboard Boxes: These are breathable and easy to stack.
Paper Grocery Bags: Great for smaller quantities of rhizomes.
Milk Crates: These offer maximum airflow if you line them with newspaper first.

The Packing Process

Place a layer of your chosen medium in the bottom of the container. Lay the rhizomes on top, making sure they are not touching each other. If one rhizome happens to develop rot, keeping them separated prevents the issue from spreading to the whole batch. Cover them with more medium and repeat the layers until the box is full.

What to do next:

Select a breathable container like a cardboard box.

Add a 2-inch layer of slightly damp peat moss or wood shavings.

Arrange rhizomes so they do not touch.

Cover completely with more storage medium.

Label the box with the variety or color so you know what is what in the spring!

Finding the Best Storage Location

The location where you keep your boxes is just as important as how you pack them. Cannas need a cool, dark, and dry spot.

The ideal temperature range is between 45°F and 55°F.

Unheated Basements: Usually the most consistent environment for bulb storage.
Root Cellars: These are perfect if they stay dry.
Attached Garages: These can work, but you must ensure the temperature never drops below freezing.

If the storage area is too warm (above 60°F), the rhizomes might think it is spring and start growing prematurely. If it is too cold (below 40°F), the tropical cells inside the rhizome can be damaged. Finding that cool middle ground ensures they stay dormant and healthy.

Monitoring Your Rhizomes Through Winter

Don't just set them and forget them! We recommend checking your stored cannas once a month. This small effort can save your entire collection.

When you check them, look for two things:

Rot: If a rhizome feels mushy or has a foul smell, remove it immediately. If the rot is only on a small tip, you can cut it off, let it dry, and put it back. But if the whole piece is soft, toss it out to protect the others.
Shriveling: If the rhizomes feel very light and look wrinkled, they may be getting too dry. You can lightly mist the storage medium with a spray bottle of water. You don't want it wet—just "barely damp" to the touch.

Most gardeners find that if they start with healthy, cured rhizomes, about 80% to 90% of them will make it through the winter perfectly. Losing a few is a natural part of the process, so don't be discouraged if one or two don't make it.

Bringing Cannas Out of Storage

When the days start to get longer and the threat of hard frost has passed, it is time to check on your cannas again. In most regions, this is in late April or May.

You can plant your rhizomes directly into the garden once the soil has warmed up to about 60°F. Cannas love heat, so there is no rush to put them in cold, damp ground. If you want to get a head start on the season, you can "wake them up" indoors.

To do this, plant the rhizomes in pots about 4 to 6 weeks before your last frost date. Place the pots in a warm, sunny window. By the time the outdoor weather is truly tropical, you will have established plants ready to jump-start your summer display.

Summary of the Canna Storage Cycle

Overwintering cannas is a cycle that gets easier every year you do it. The more you work with these plants, the more you will recognize their needs. By taking the time to trim the roots and cure the rhizomes properly, you are setting yourself up for a garden full of high-impact color.

At Longfield Gardens, we believe that gardening should be a rewarding experience. Saving your own canna lilies is a great way to participate in the full life cycle of your plants. It adds a sense of continuity to your landscape and gives you the satisfaction of seeing your garden grow in size and beauty every year.

Key Takeaway: Success with canna storage comes down to three basics: a thorough curing period, trimming off old roots for cleanliness, and maintaining a cool, breathable storage environment.

Conclusion

Storing canna lilies is a simple and effective way to enjoy these tropical beauties year after year. While it might seem like a lot of steps at first, the process of digging, cleaning, and packing quickly becomes a rhythmic part of the autumn garden wrap-up. Remember that the roots you see in the fall are temporary, and the real magic is stored inside the firm, healthy rhizome.

By following these steps, you can look forward to a spectacular show of foliage and flowers every summer.

Wait for the first frost to trigger dormancy.
Trim the stringy roots to keep things clean and prevent rot.
Cure the rhizomes for several days to toughen the skin.
Store in a cool, dark, and breathable spot.

We hope this guide makes your fall gardening tasks feel easy and achievable. For more tips on growing beautiful bulbs and perennials, feel free to explore our other guides. Happy gardening, and enjoy the anticipation of next year's blooms!

FAQ

Should I wash the soil off my canna rhizomes before storing them?

You can wash them if the soil is heavy or clay-like, as this helps you see the rhizome's health and where to divide it. However, if you do wash them, you must be very careful to let them dry completely during the curing process. Many gardeners find that simply brushing off the dry soil after a few days of curing is sufficient and reduces the risk of trapped moisture. For more growing tips, see All About Cannas.

Can I leave the roots on the canna bulb during the winter?

Yes, you can leave the roots on if you prefer, as it won't necessarily harm the plant. However, trimming them makes the rhizomes much easier to pack into boxes and reduces the amount of debris in your storage area. Since the plant will grow entirely new roots in the spring, the old ones are not needed for next year's growth.

How do I know if my canna rhizomes have rotted during storage?

A healthy rhizome should feel firm to the touch, similar to a fresh ginger root or a potato. If you squeeze a rhizome and it feels soft, mushy, or "squishy," it has likely rotted. Another sign is a dark, water-soaked appearance or a noticeable moldy smell. Any mushy rhizomes should be removed immediately to prevent the rot from spreading to healthy ones. If you want more ideas for growing and enjoying these plants, see Fresh Ideas for Growing Cannas in Your Garden.

What is the best material to pack canna bulbs in?

The most popular materials are peat moss, wood shavings (like those used for pet bedding), or vermiculite. These materials are excellent because they provide insulation and can absorb or release small amounts of moisture to keep the rhizomes stable. Some people also have great success simply wrapping each rhizome in several layers of dry newspaper and placing them in a cardboard box.