How to Store Canna Bulbs for the Winter: A Simple Guide

Table of Contents

1. Introduction
2. Understanding When to Dig
3. The Best Timing for Harvest
4. How to Dig and Prepare Canna Rhizomes
5. The Curing Phase
6. Choosing Your Storage Medium
7. Finding the Ideal Storage Location
8. Monitoring Your Cannas Through Winter
9. Overwintering Cannas in Containers
10. Dividing Rhizomes for More Plants
11. Preparing for Spring Replanting
12. Common Myths About Canna Storage
13. Conclusion
14. FAQ

Introduction

Few plants bring as much tropical flair and vibrant energy to a backyard as cannas. Their oversized, paddle-shaped leaves and brilliant blossoms in shades of red, orange, and yellow make any garden feel like a private oasis. At Longfield Gardens, we believe these spectacular cannas are some of the most rewarding flowers you can grow. Because they are so easy to care for during the summer, it is only natural to want to keep them around for the following year.

Saving your canna rhizomes—often called bulbs—is a straightforward process that ensures you can enjoy your favorite varieties season after season. For planting basics, see our All About Cannas guide. Whether you are a beginner or a seasoned gardener, the steps for overwintering these tender perennials are simple to master. This guide covers everything from the perfect timing for the harvest to the best ways to pack and store your plants until spring returns. By following these easy steps, you can protect your investment and look forward to even bigger, bolder displays next year.

Storing canna rhizomes is a practical and satisfying way to extend the life of your garden while preparing for a successful spring planting.

Understanding When to Dig

The decision to dig up your canna rhizomes depends largely on where you live and the local weather patterns. Cannas are tropical plants that thrive in warmth, but they are sensitive to freezing temperatures. In USDA hardiness zones 8 and warmer, these plants can often stay in the ground year-round. However, if you live in zone 7 or colder, the winter soil will likely get cold enough to damage the fleshy roots.

Even in warmer zones, some gardeners choose to dig up their cannas to divide them or to clear space for winter-blooming bulbs. If you are in a cold climate, digging is a necessary step to keep the plants alive. The goal is to let the plant grow for as long as possible to store energy, but to get the rhizomes safely tucked away before the ground freezes solid.

The Best Timing for Harvest

The most common question we hear is exactly when to start the digging process. Nature provides a very clear signal: the first frost. While cannas love the heat of late summer, the first light touch of autumn frost will turn their lush green or bronze foliage to black or brown.

This change might look a bit sad at first, but it is actually a helpful sign. The frost tells the plant that the growing season is over and it is time to go dormant. Waiting for this frost allows the rhizome to pull the last bits of energy from the leaves and stalks, which helps it survive the long winter months.

You do not need to rush out the second the frost hits. You generally have a window of a few days or even a week before the ground begins to freeze. Aim to harvest when the soil is relatively dry, as this makes it much easier to shake off excess dirt and keeps the process cleaner.

How to Dig and Prepare Canna Rhizomes

Once the foliage has been nipped by frost, you are ready to begin. The process of lifting the rhizomes is simple, but it requires a gentle hand to ensure the plants remain healthy for their winter nap.

Cutting Back the Stalks

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 small "handle" makes the rhizomes easier to move around and helps you identify which side is the top when it comes time to replant in the spring. Discard the dead foliage in your compost pile or yard waste bin.

Lifting the Clumps

Cannas grow from rhizomes, which are thick, fleshy underground stems that spread horizontally. Over a single summer, one small rhizome can grow into a large, heavy clump. To lift them safely, use a garden fork or a sturdy shovel.

Start digging about a foot away from the base of the stems to avoid slicing through the tender rhizomes. Gently pry upward from several sides until the entire clump loosens and can be lifted from the earth. If the soil is heavy or wet, the clumps can be quite heavy, so take your time and lift with your legs.

Cleaning the Rhizomes

Once the cannas are out of the ground, shake them gently to remove large clods of soil. You can use your hands to brush away more dirt, but avoid scrubbing them or using a high-pressure hose. The "skin" of a canna rhizome is relatively thin and can be easily bruised.

If the soil is particularly sticky, a light rinse with a garden hose is fine, but make sure they dry thoroughly afterward. Any wounds or scrapes on the surface can become entry points for rot, so handle them like you would a piece of fresh fruit.

Key Takeaway: Handle with Care The most important part of the digging process is avoiding physical damage to the rhizomes. Small nicks are usually fine, but deep gouges can lead to problems in storage. Always dig wider than you think you need to.

The Curing Phase

Curing is a step that many new gardeners skip, but it is essential for long-term storage success. Curing is simply the process of letting the rhizomes air-dry in a protected spot for a short period. For a step-by-step look at this process, see What to Do With Canna Lily Bulbs. This allows the outer skin to toughen up and any small nicks to "callous" over.

Find a spot that is dry, well-ventilated, and out of direct sunlight. A garage, a shed, or even a covered porch works perfectly. Spread the rhizomes out in a single layer on a piece of cardboard or a newspaper. Do not stack them, as you want air to reach all sides.

Let the cannas cure for about 7 to 10 days. During this time, the remaining soil will dry up and fall off easily, and the cut stems will start to shrivel slightly. Once they feel dry to the touch and the outer surface seems firm, they are ready to be packed away.

Choosing Your Storage Medium

To keep cannas healthy through the winter, they need a "Goldilocks" environment: not too wet and not too dry. If the storage area is bone-dry, the rhizomes will shrivel and die. If it is too damp, they will rot. We use a storage medium to act as a buffer, holding just enough moisture to keep the rhizomes alive without encouraging mold.

There are several great options for storage media, and you likely have one of them on hand:

• Peat Moss: This is the most common choice. It is lightweight and holds moisture well.
• Vermiculite or Perlite: These are sterile and excellent for moisture control.
• Wood Shavings: The kind sold for pet bedding works well as it allows for good airflow.
• Newspaper: Wrapping individual rhizomes in layers of newspaper is an old-fashioned but effective method.

Packing the Rhizomes

Once you have chosen your medium, find a container that allows for some air circulation. Cardboard boxes, paper bags, or plastic bins with holes drilled in the sides are all excellent choices. Avoid airtight plastic containers, as trapped moisture is the leading cause of rot.

1. Place a 2-inch layer of your chosen medium in the bottom of the container.
2. Lay the rhizomes on top of the medium. It is okay if they are close together, but try to keep them from touching each other directly.
3. Cover the rhizomes with more medium until they are completely buried.
4. If you have many cannas, you can create multiple layers, but avoid making the box so heavy that it is difficult to move.
5. Label the box with the variety name or flower color so you know what you are planting next year.

What to Do Next

• Gather your containers and storage medium before the first frost.
• Check your labels to make sure you know which colors are which.
• Prepare a space in your basement or garage for the curing phase.
• Mark your calendar for a monthly storage check-up.

Finding the Ideal Storage Location

The location where you keep your boxes is just as important as how you pack them. Cannas need to stay dormant, which requires a cool environment. However, they cannot survive a freeze.

The ideal temperature for storing canna rhizomes is between 40°F and 55°F. For most people, a cool basement, an unheated crawl space, or a root cellar is the perfect spot. An attached garage can also work, provided the temperature stays above freezing. Avoid storing them near a furnace, water heater, or any other heat source, as this will dry them out too quickly or trick them into thinking it is time to grow.

Monitoring Your Cannas Through Winter

While it is tempting to "set it and forget it," checking on your cannas once a month is a great habit. This allows you to catch any potential issues before they spread.

When you check the boxes, look for two things:

1. Signs of Rot: If a rhizome feels soft, mushy, or has a foul smell, remove it immediately. Rot can spread from one rhizome to another, so taking out the "bad apple" protects the rest of the batch.
2. Signs of Shriveling: If the rhizomes look very wrinkled or feel exceptionally light and brittle, they are getting too dry. Use a spray bottle to lightly mist the storage medium with water. You don't want it to be wet—just slightly damp to the touch.

If you find that your storage area is consistently too dry, you can loosely fold over the top of the paper bag or box to help retain moisture. If it feels too damp, open the top to let more air in.

Overwintering Cannas in Containers

If you grow your cannas in large pots or decorative containers, the process is even easier. For a smaller, pot-friendly option, browse Short Cannas. You don't necessarily have to dig the rhizomes out of the soil.

Once the frost kills the foliage, cut the stalks back to the soil level as you would with in-ground plants. Move the entire pot into a cool, frost-free area like a basement or garage. Stop watering the pot entirely. The soil in the container will act as the storage medium.

In the spring, about six to eight weeks before the last frost, you can bring the pot back into a warm, sunny spot and begin watering it again to "wake up" the plants. This is a great way to get a head start on the season, as the plants will already be established in their home.

Dividing Rhizomes 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 often result in a clump with five or ten distinct growing points by October. If you want a mid-sized garden display next year, take a look at Medium Cannas.

You can divide these clumps either in the fall before you store them or in the spring before you plant them. Most gardeners prefer to wait until spring because the "eyes" (the small bumps where new growth will emerge) are easier to see.

To divide them, simply use a clean, sharp knife to cut the rhizome into sections. Each section should have at least one or two healthy-looking eyes. If you divide them in the fall, let the cut ends dry and callous for a few days before packing them away. This is an easy, free way to expand your garden or share your favorite varieties with neighbors and friends.

Preparing for Spring Replanting

As winter winds down and the ground begins to warm, your cannas will be ready to head back outside. At Longfield Gardens, we recommend waiting until the danger of frost has completely passed and the soil temperature has reached at least 60°F. If you want to get a jump on the season, read Starting Canna Lily Bulbs Indoors. Cannas are heat-lovers, and they won't do much until the ground is cozy.

A few weeks before planting, you can take the rhizomes out of storage to inspect them one last time. Discard any that didn't make it through the winter and keep the firm, healthy ones. If you want earlier blooms, you can "start" your cannas indoors by planting them in pots and placing them in a sunny window about a month before your last frost date. By the time the weather is right for outdoor planting, you will already have several inches of lush green growth.

Common Myths About Canna Storage

There is a lot of advice online about storing tropical plants, and it can sometimes be confusing. One common myth is that you must wash every speck of soil off the rhizome with a scrub brush. In reality, a little bit of leftover soil is harmless and often helps protect the rhizome.

Another myth is that cannas need to be stored in "bone-dry" conditions. While we want to avoid rot, a completely dry rhizome will eventually die. Think of the rhizome as a living thing that is simply "sleeping." Like any living thing, it needs a tiny bit of moisture to maintain its internal structure.

Finally, don't worry if you don't have a professional "root cellar." Most modern homes have a corner in the basement or a closet on an exterior wall that stays perfectly cool. As long as the temperature stays in that 40°F to 55°F range, your cannas will be just fine.

Conclusion

Learning how to store canna bulbs for the winter is a simple skill that transforms these tropical beauties from one-season wonders into long-term garden staples. By following the natural cues of the first frost and providing a cool, stable environment for the winter, you ensure your garden will be filled with color year after year. The satisfaction of seeing those first green shoots emerge in the spring from rhizomes you saved yourself is one of the many joys of gardening.

• Wait for the first frost to signal dormancy before digging. For a taller backdrop next year, browse Tall Cannas.
• Cure the rhizomes for a week to toughen the skin and prevent rot. For signature striped foliage, try Canna Tall Tropicanna.
• Store in a breathable container with a medium like peat moss or wood shavings. For a bright gold-toned option, see Canna Tall Tropicanna Gold.
• Keep the storage area cool (40-55°F) and check for moisture once a month. For a classic red-orange bloomer, shop Canna Tall Australia.

The beauty of cannas is that they are incredibly resilient. Once you get the hang of the basic storage steps, you'll find that these plants are more than happy to return each year, bigger and more beautiful than before.

At Longfield Gardens, we are here to help you grow a garden you love, and our 100% Quality Guarantee is part of that promise. If you are looking to add new colors or heights to your collection, we invite you to explore our selection of premium canna rhizomes and other summer-blooming favorites. Gardening should be a rewarding journey, and we are proud to provide the quality plants and practical advice you need to succeed.

FAQ

Can I store canna rhizomes in plastic bags?

You can use plastic bags, but they must have several holes for ventilation. Airtight bags trap moisture, which quickly leads to rot and mold. Most gardeners find that paper bags or cardboard boxes are safer options because they naturally allow the rhizomes to breathe while still holding in enough moisture to prevent shriveling.

What should I do if my stored cannas start growing in February?

If you see sprouts early, it usually means your storage area is a bit too warm. You can try moving the boxes to a cooler spot to slow them down. If the sprouts are already several inches long, you can pot them up in soil and keep them in a bright window as houseplants until it is safe to move them outside.

Is it necessary to rinse the rhizomes after digging them up?

Rinsing is not strictly necessary unless your soil is very heavy clay that won't shake off. In most cases, letting the soil dry for a day and then gently brushing it off with your hands is better for the plant. If you do rinse them, ensure they are 100% dry before you pack them away, as moisture is the biggest threat during storage.

How long do canna rhizomes last in storage?

If stored under the right conditions (cool, dark, and slightly humid), canna rhizomes will easily last through the winter and early spring, roughly 5 to 7 months. They are not meant to be stored for multiple years, however. They need a growing season to replenish their energy stores, so they must be planted out every spring to remain viable.