How Do You Store Canna Lily Bulbs for the Winter?

Table of Contents

1. Introduction
2. Understanding the Canna Rhizome
3. Knowing When to Lift Your Cannas
4. Identifying Your Hardiness Zone
5. Step-by-Step: How to Dig Canna Rhizomes
6. Cleaning and Curing for Success
7. Choosing the Best Storage Medium
8. Ideal Winter Storage Locations
9. Overwintering Cannas in Containers
10. Monitoring Your Bulbs During Winter
11. Dividing Your Cannas for More Plants
12. Preparing for Spring Planting
13. Conclusion
14. FAQ

Introduction

Canna lilies are the undisputed stars of the summer garden. Their bold, tropical foliage and vibrant flowers bring an exotic energy to any landscape, from backyard borders to poolside containers. At Longfield Gardens, we love how these plants transform a garden into a lush retreat with very little effort. While cannas thrive in the heat of summer, they are tender perennials that cannot survive freezing temperatures in most parts of the country.

Learning how do you store canna lily bulbs for the winter is a rewarding skill that allows you to enjoy your favorite varieties year after year. Instead of buying new plants every spring, you can easily "overwinter" the ones you already have. This process is simple, cost-effective, and surprisingly satisfying. By following a few basic steps, you can keep your canna rhizomes healthy and dormant until the warm weather returns.

This guide will walk you through everything you need to know about lifting, curing, and storing your canna lilies. Whether you are a beginner or an experienced gardener, you will find that protecting these tropical beauties is an easy addition to your fall routine. Our goal is to help you feel confident in preserving your garden’s vibrant colors for next season. For a mixed selection, browse Assorted Cannas.

Understanding the Canna Rhizome

Before we dive into the storage process, it is helpful to know what you are actually handling. Although many gardeners call them "bulbs," cannas actually grow from rhizomes. A rhizome is a thick, fleshy underground stem that grows horizontally. It stores energy and water for the plant, which is why cannas are so resilient during the hot summer months.

These rhizomes are quite sturdy, but they are also full of moisture. This high water content is what makes them sensitive to frost. If the water inside the rhizome freezes, it expands and destroys the plant's cell walls, leading to rot. This is why digging them up in colder climates is essential.

Over the course of a single growing season, a small rhizome can grow significantly. It will often produce several "eyes" or growth points. When you dig them up in the fall, you might find that your single plant has turned into a large clump. This natural multiplication is one of the best parts of growing cannas, as it gives you more plants to use or share with friends the following year. For more options, browse Medium Cannas.

Knowing When to Lift Your Cannas

Timing is everything when it comes to overwintering cannas. You want to give the plants as much time as possible to store energy, but you must get them out of the ground before a deep freeze sets in. For more options, browse Tall Cannas.

The best signal comes from nature itself. In most regions, you should wait until a light frost has touched the foliage. You will notice the leaves turn brown or black after a cold night. This may look a bit sad, but it is actually a good thing. The frost sends a signal to the plant that it is time to go dormant.

If you live in an area that does not get frost until very late in the year, you can simply wait until the foliage begins to yellow and die back naturally in late autumn. The key is to lift them while the ground is still workable and before a hard freeze reaches the rhizomes themselves. A light surface frost will not hurt the buried rhizomes, but frozen soil will.

Key Takeaway: Wait for the first light frost to blacken the leaves before digging. This ensures the plant has finished storing energy for the winter.

Identifying Your Hardiness Zone

Whether you need to dig up your cannas depends entirely on where you live. The USDA Plant Hardiness Zone Map is the best tool for determining if your plants can stay in the ground. USDA Plant Hardiness Zone Map

• Zones 8 to 10: In these warmer climates, cannas are generally hardy. You can leave them in the ground year-round. Many gardeners simply cut the stalks back to the ground and perhaps add a thin layer of mulch for aesthetics.
• Zone 7: This is a "buffer" zone. In mild winters, cannas may survive in the ground with a thick 6-to-8-inch layer of mulch (like straw or shredded leaves). However, a particularly cold winter can still kill them. If you have a rare or favorite variety, lifting them is the safest bet.
• Zones 3 to 6: In these regions, the ground freezes deep enough to destroy the rhizomes. Storing them indoors is necessary if you want to keep them for the next year.

If you aren't sure which zone you are in, you can check your local weather service or look up your zip code on a hardiness zone map. Knowing your zone takes the guesswork out of fall garden chores.

Step-by-Step: How to Dig Canna Rhizomes

Once the first frost has arrived, it is time to get to work. Digging up cannas is not a delicate operation, but you should move carefully to avoid slicing the rhizomes.

1. Cut Back the Foliage

Start by cutting the stalks down to about 3 to 4 inches above the soil line. Removing the heavy, frost-damaged leaves makes the digging process much easier. It also gives you a "handle" to help lift the clump later. Use sharp garden shears or a lopper for thick stalks.

2. Loosen the Soil

Cannas have wide-reaching root systems. Start digging about 6 to 10 inches away from the base of the plant to avoid hitting the rhizomes. Use a garden fork or a sturdy spade. Dig all the way around the plant to loosen the root ball from the surrounding earth.

3. Lift the Clump

Gently pry the clump upward. You may need to rock the shovel or fork back and forth to break the suction of the soil. Once the clump is loose, lift it out of the hole. If the clump is very large, you can carefully break it into two or three smaller sections to make it easier to carry.

4. Remove Excess Soil

Shake the clump gently to remove large pieces of dirt. You can also use your hands to brush away loose soil. Do not worry about getting them perfectly clean yet; the goal is just to make them manageable for the next step.

Cleaning and Curing for Success

After the rhizomes are out of the ground, they need a little bit of preparation before they go into storage. This stage is called "curing," and it is the most important step for preventing rot. For a more detailed winter-storage overview, see How to Keep Canna Bulbs Over Winter.

Washing the Rhizomes

Some gardeners prefer to wash their cannas with a garden hose to remove all soil. This can help you see any signs of damage or pests. If you choose to wash them, use a gentle stream of water. Avoid scrubbing the rhizomes, as their "skin" is relatively soft and easy to bruise. Wounds from scrubbing can become entry points for fungus during the winter.

The Curing Process

Curing is simply allowing the rhizomes to air dry in a protected area. This process helps the outer skin toughen up and allows any cuts or nicks to "callus" over.

Place your cleaned rhizomes in a single layer on a piece of cardboard, a screen, or a newspaper. Choose a location that is dry, well-ventilated, and out of direct sunlight. A garage, shed, or basement works well, provided the temperature stays between 60°F and 80°F.

Let the rhizomes dry for about 3 to 7 days. You will know they are ready when the surface feels dry to the touch and any remaining bits of soil have turned into dry dust that easily falls off.

Next Steps for Curing:

• Move rhizomes to a dry, shaded area.
• Lay them out in a single layer (don't stack them).
• Wait 3–7 days until the outer skin feels firm.
• Gently brush off any remaining dry soil.

Choosing the Best Storage Medium

Once your cannas are cured, they need a "home" for the winter. You cannot simply leave them out in the open air, as they will eventually shrivel up and die. The goal is to keep them dormant and slightly hydrated without letting them get damp enough to rot. For a mixed selection, browse Assorted Cannas.

We recommend using a packing material that breathes but holds a tiny bit of moisture. Popular choices include:

• Peat Moss: This is the most common choice. It is naturally sterile and does a great job of regulating moisture.
• Vermiculite or Perlite: These lightweight minerals are excellent for drainage and aeration.
• Wood Shavings: Large flakes (like the kind used for animal bedding) provide good air circulation. Avoid fine sawdust, which can pack too tightly and hold too much moisture.
• Newspaper: If you only have a few rhizomes, you can wrap each one individually in several layers of dry newspaper.

Place a 2-inch layer of your chosen medium in the bottom of a cardboard box, a plastic bin with air holes, or a paper grocery bag. Lay the rhizomes on top so they are not touching each other. Cover them with more medium and repeat the layers until the container is full.

Ideal Winter Storage Locations

Where you put your boxes of cannas is just as important as how you pack them. The environment needs to be cool and dark. For a broader winter-storage guide, see Winter Storage for Tender Bulbs and Tubers.

The ideal temperature for storing canna bulbs is between 40°F and 55°F. If the area is too warm, the plants might try to start growing too early. If it is too cold, they will freeze.

• Unheated Basements: Usually the perfect spot. They stay cool and have enough humidity to prevent total dehydration.
• Crawl Spaces: These often maintain a very consistent temperature throughout the winter.
• Cool Closets: If you live in an apartment or a house without a basement, an interior closet far from a heater can work.
• Root Cellars: The traditional choice for a reason—they provide the exact conditions these plants need.

Avoid storing cannas in a garage that is not insulated. If the temperature in the garage drops below freezing during a winter storm, your rhizomes will be lost. Likewise, avoid the attic, which can fluctuate wildly in temperature.

Overwintering Cannas in Containers

If you grow your cannas in pots, you have a shortcut! You do not necessarily have to dig them up. Container-grown cannas can be stored right in their pots. For more container tips, see How to Grow Summer Bulbs in Containers.

Once the frost hits and you have cut back the foliage, move the entire pot to a cool, dark place like a basement or garage. Stop watering the plant entirely. The soil will dry out, and the plant will go into a deep sleep.

In the spring, you can bring the pot back out into the sun, give it a good soak, and the rhizomes will usually wake up and start growing again. Every two or three years, however, you should still remove the plants from the pot to divide them. Otherwise, they will become "root-bound," and the blooming will decrease because the plant has run out of space and nutrients.

Monitoring Your Bulbs During Winter

While your cannas are in storage, they are mostly "set and forget," but a quick monthly check is a smart move. This helps you catch any issues before they spread to the whole batch.

Open your storage boxes once a month and take a look. You are looking for two things: rot and shriveling.

• If you see rot: If a rhizome feels mushy or has visible mold, remove it immediately. If only a small part is affected, you can sometimes cut the rotten part away with a clean knife and let the healthy part dry out before putting it back. However, if the whole piece is soft, throw it away so it doesn't infect its neighbors.
• If they look shriveled: If the rhizomes look like wrinkled raisins, they are too dry. Use a spray bottle to lightly mist the packing medium with water. You don't want it wet—just slightly damp to the touch. This provides just enough humidity to keep the rhizomes plump.

Most gardeners at Longfield Gardens find that they lose a few rhizomes every year. Do not be discouraged if a few don't make it. As long as the majority of your harvest remains firm and healthy, you are doing a great job.

Dividing Your Cannas for More Plants

One of the most exciting parts of storing cannas is seeing how much they have grown. A single rhizome planted in May can become a massive clump by October. You can divide these clumps to create more plants for your garden. For step-by-step help, see How to Divide and Store Canna Bulbs: A Winter Guide.

You can divide cannas either in the fall (before storage) or in the spring (before planting). Many people prefer spring because the "eyes" or growth buds are easier to see as the plant wakes up.

To divide them:

1. Look for the "eyes"—these look like small, rounded bumps or points on the rhizome.
2. Use a sharp, clean knife to cut the rhizome into sections.
3. Ensure each section has at least one or two healthy eyes.
4. Let the cut ends dry for a day before planting to prevent infection.

This is the easiest way to expand your garden or give gifts to fellow gardeners. It keeps the plants healthy, as overgrown clumps eventually produce smaller flowers.

Preparing for Spring Planting

When the days start getting longer and the threat of frost is a distant memory, it is time to wake up your cannas. This usually happens in late April or May, depending on your local climate. For more planting guidance, see Canna Lily Bulbs: How to Plant for Vibrant Summer Blooms.

You can give your cannas a head start by "pre-starting" them indoors. About 4 to 6 weeks before the last frost, take the rhizomes out of storage and plant them in pots with potting soil. Place them in a sunny window or under grow lights. By the time the outdoor soil is warm enough, you will have established plants ready to go into the ground.

If you prefer to plant directly into the garden, wait until the soil temperature reaches at least 60°F. Cannas love warmth, and they will sit dormant in cold, wet soil. Patience is rewarded with faster growth once the summer sun arrives.

Spring Checklist:

• Inspect all rhizomes and discard any soft ones.
• Divide large clumps if you didn't do it in the fall.
• Optional: Start indoors 4–6 weeks early for faster blooms.
• Plant outdoors only after the soil is warm and frost is gone.

Conclusion

Storing canna lily bulbs for the winter is a simple and rewarding process that preserves the beauty of your summer garden. By following the natural signals of the seasons, you can successfully lift, cure, and house your rhizomes until the warm weather returns. This practice not only saves money but also allows you to cultivate larger, more impressive displays every year as your collection grows. Explore cannas to find your next planting.

At Longfield Gardens, we believe that gardening should be a source of joy, not a cause for stress. While the idea of "digging and storing" might sound like a big task, it quickly becomes a favorite fall ritual. There is something deeply satisfying about tucking your plants away for a winter nap, knowing they will return even stronger next year.

Key Takeaways for Success:

• Dig after the first light frost kills the leaves.
• Cure the rhizomes for several days in a dry, airy spot.
• Store in a cool, dark location between 40°F and 55°F.
• Check periodically for moisture or rot during the winter months.

We encourage you to try overwintering your cannas this season. With just a little bit of care, those tropical colors will be ready to brighten your landscape again next summer.

FAQ

Can I store canna lily bulbs in a plastic bag?

Yes, but you must ensure there is airflow to prevent rot. Use a plastic bag only if you poke several holes in the sides and fill it with a moisture-regulating medium like peat moss. A paper bag or cardboard box is often a safer choice because these materials naturally "breathe" better than plastic.

Do I have to wash the dirt off the rhizomes before storing them?

It is not strictly necessary to wash them, but it is a good idea. Washing helps you inspect the rhizomes for pests or diseases. If you skip the wash, make sure to shake off as much soil as possible and let the remaining dirt dry completely during the curing phase so it can be brushed away.

What happens if I forget to dig up my cannas before a hard freeze?

A light frost that kills the leaves is fine, but a hard freeze that turns the ground solid can kill the rhizomes. If you experience a sudden deep freeze, dig them up as soon as the soil thaws. Inspect them carefully; if they are mushy or watery, they have likely been damaged beyond repair and should be discarded.

How long can canna lily rhizomes stay in storage?

Canna rhizomes are meant to stay in storage for the duration of the winter dormant season, usually 4 to 6 months. They should be replanted in the spring once the soil warms up. They cannot stay in storage indefinitely, as they will eventually run out of stored energy or completely dry out.