Storing Canna Bulbs Indoors for Next Season

Table of Contents

1. Introduction
2. Understanding the Canna Rhizome
3. Timing Your Harvest Correctly
4. Tools and Materials for Success
5. How to Lift Canna Rhizomes Safely
6. The Curing Process
7. Preparing for Indoor Storage
8. Finding the Right Location
9. Overwintering Potted Cannas
10. Winter Checkups
11. Dividing Cannas for More Plants
12. Moving Cannas Back Outdoors
13. Conclusion
14. FAQ

Introduction

There is something truly satisfying about watching the bold, tropical foliage of a canna lily unfurl in the summer sun. These plants bring an exotic energy to the garden that few other perennials can match. While they are incredibly resilient during the heat of July and August, most varieties cannot survive the biting cold of a northern winter. Learning the process of storing canna bulbs indoors allows you to keep your favorite varieties year after year.

At Longfield Gardens, we want to help you preserve the beauty of your landscape with as little stress as possible. If you want a broader step-by-step refresher, our canna bulb storage guide is a helpful companion read. Storing these fleshy roots—technically called rhizomes—is a straightforward task that any gardener can master. This guide is designed for home gardeners in cooler climates who want to protect their investment and enjoy even bigger, more impressive blooms next summer. By following a few simple steps, you can ensure your cannas rest safely through the winter and return with vigor in the spring.

Understanding the Canna Rhizome

To store cannas successfully, it helps to know what you are actually handling. Although most gardeners refer to them as "bulbs," cannas grow from rhizomes. A rhizome is a thick, fleshy underground stem that stores energy and nutrients for the plant. If you look closely at a canna rhizome, you will see "eyes" or small bumps. These are the growth points where new stems will emerge next year.

Because these structures are full of water, they are very sensitive to freezing temperatures. When the water inside the rhizome freezes, it expands and destroys the plant tissues, leading to rot. This is why lifting and storing them indoors is essential in USDA hardiness zones 7 and colder. To check your own gardening region, use the Hardiness Zone Map. In warmer regions, like zones 8 through 10, cannas can often stay in the ground year-round with a bit of mulch, but for the rest of us, a cozy indoor spot is required.

Timing Your Harvest Correctly

One of the most important factors in successful storage is knowing when to bring your plants inside. You do not want to rush the process, as the plant uses the late summer and early autumn to store up energy for the following season.

The best time to dig up your cannas is shortly after the first light frost of the season. You will know the time is right when the lush green or bronze leaves turn black or brown and begin to wilt. This change in appearance might look disappointing, but it is actually a helpful signal from nature. The frost tells the plant to stop growing and move its energy down into the rhizome for dormancy.

If you live in an area where a hard freeze happens suddenly, try to get your rhizomes out of the ground before the soil itself freezes solid. A light surface frost that nips the leaves is fine, but you want to protect the underground portion from extreme cold.

Key Takeaway: Wait for the first frost to blacken the foliage before digging. This ensures the rhizome has stored maximum energy for next year’s growth.

Tools and Materials for Success

Before you head out to the garden, gather a few basic supplies. Having everything ready makes the process much faster and more enjoyable. You likely already have most of these items in your garden shed.

• A garden fork or sturdy shovel: A garden fork is often preferred because it is less likely to slice through the rhizomes than a flat spade.
• Pruning shears or garden snips: You will need these to trim away the spent stalks and foliage.
• A garden hose: This is helpful for rinsing off heavy clay soil, though it is not always necessary if your soil is sandy and loose.
• Storage containers: Cardboard boxes, plastic bins with air holes, or even heavy paper bags work well.
• Packing material: To keep the rhizomes from drying out completely, you will need a medium like peat moss, vermiculite, perlite, or clean wood shavings.
• Labels and a waterproof marker: It is very easy to forget which variety is which once the leaves are gone. Labeling is a step you will be glad you took come spring.

How to Lift Canna Rhizomes Safely

When you are ready to dig, start by cutting the stalks down. Use your shears to trim the stems to about 2 to 4 inches above the soil line. This gives you a "handle" to grab while digging but removes the bulky, unnecessary foliage.

Next, use your garden fork to loosen the soil around the clump. Cannas can spread significantly during a single growing season, so start digging about a foot away from the base of the stems. Work your way around the plant in a circle, gently prying upward. The goal is to lift the entire mass of rhizomes out of the ground in one piece without bruising or cutting the flesh.

Once the clump is lifted, shake it gently to remove large chunks of soil. If the soil is very wet or clingy, you can use a hose to wash it away. However, do not scrub the rhizomes. Their "skin" is relatively thin, and any wounds created during cleaning can become entry points for fungus or rot during the winter months.

What to Do Next

• Trim stalks to 3 inches.
• Dig a wide circle around the plant to avoid damage.
• Lift the clump gently from underneath.
• Shake or rinse off excess soil.

The Curing Process

You should never move freshly dug rhizomes directly into a sealed storage container. They contain a high amount of moisture and need a short period to "cure." Curing is simply a fancy word for letting the outer skin dry and toughen up.

Find a dry, well-ventilated spot that is protected from rain and frost. A garage, a garden shed, or a covered porch works perfectly. Spread the rhizomes out in a single layer on a piece of cardboard or a newspaper. Let them sit there for several days, up to a week.

During this time, the cut ends of the stalks will dry out and the outer surface of the rhizome will become less prone to bruising. If you notice any soft spots or damaged areas that look like they are starting to decay, trim them off with a clean knife before the curing process is finished.

Preparing for Indoor Storage

Once the rhizomes are cured, they are ready for their winter home. The goal of storage is to keep the plant dormant—not too wet, which causes rot, and not too dry, which causes the rhizome to shrivel and die.

Choosing a Medium

Most successful gardeners use a "packing medium" to surround the rhizomes. This acts as insulation and helps maintain a very low level of humidity.

• Peat Moss: A classic choice that holds just enough moisture.
• Wood Shavings: Often used for animal bedding, these are breathable and clean.
• Newspaper: You can wrap individual rhizomes in layers of dry newspaper.
• Vermiculite or Perlite: These are sterile and excellent for preventing rot.

Packing the Bins

Place a layer of your chosen medium in the bottom of a cardboard box or plastic bin. Lay the rhizomes on top so they are not crowded. It is best if they do not touch each other; this way, if one starts to rot, the problem won't spread to its neighbors. Cover them with more packing material until they are completely tucked in.

If you use plastic bins, ensure there are holes in the sides or leave the lid slightly ajar. Air circulation is vital. If the container is airtight, moisture will build up and lead to mold.

Key Takeaway: Pack rhizomes in a breathable medium like peat moss or wood shavings, ensuring they do not touch one another to prevent the spread of rot.

Finding the Right Location

The environment where you keep your storage bins is just as important as how you pack them. Cannas need a spot that is cool and dark. The ideal temperature range is between 40°F and 55°F.

If the area is too warm, the plants might try to start growing prematurely. If it is too cold and drops below freezing, the rhizomes will be destroyed. Common successful locations include:

• An unheated basement or crawl space.
• A cool closet located on an exterior wall.
• An insulated garage that stays above freezing.
• A root cellar.

Avoid spots near heaters, furnaces, or water heaters, as these areas are usually much too dry and warm for dormant plants.

Overwintering Potted Cannas

If you grow your cannas in large pots or containers, you have a slightly easier path. You do not necessarily have to dig the rhizomes out of the soil. Once the frost hits the leaves, cut the stems back to the soil level just as you would with garden-planted cannas. For more inspiration on container-friendly options, take a look at Canna Tall Pretoria.

Move the entire pot into a cool, frost-free area like a basement or garage. The soil in the pot will act as the storage medium. You won't need to water the pot throughout the winter; the goal is to keep the soil dry so the plant stays dormant. In the spring, you can bring the pot back out into the sun, begin watering, and wait for the new shoots to appear.

Winter Checkups

Storing canna bulbs indoors is not a "set it and forget it" task. It is a good idea to check on your plants about once a month throughout the winter. This only takes a few minutes but can save your entire collection.

Open the boxes and feel a few of the rhizomes. If they feel firm and plump, everything is going well. If you see any that have become soft, mushy, or smell bad, remove them immediately and throw them away. This prevents rot from spreading.

If the rhizomes look very shriveled or feel excessively light, they may be drying out too much. You can lightly mist the packing medium with a spray bottle of water. Do not soak it; you just want to add a tiny bit of humidity back into the box.

Winter Maintenance Checklist

• Check bins once a month for soft spots.
• Discard any rhizomes showing signs of mold or rot.
• Lightly mist the packing material if rhizomes appear shriveled.
• Ensure the storage temperature remains above 40°F.

Dividing 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 often turns into a large mass by October. Winter storage is the perfect time to think about dividing these clumps, which is a simple way to get more plants for free.

You can divide the clumps either in the fall before you pack them away or in the spring before you replant. To divide them, simply use a sharp, clean knife to cut the rhizome into smaller pieces. Each piece must have at least one "eye" or growing point to produce a new plant. If you are looking for a ready-made planting mix, the Canna Assorted Mix - Bulk Offer is a useful option to compare.

If you divide them in the fall, let the cut ends dry for an extra day before packing them in the medium. This allows the "wound" to callus over, which protects the plant while it is dormant.

Moving Cannas Back Outdoors

As the days get longer and the ground begins to warm in the spring, it is time to think about replanting. Cannas are tropical, so they are in no hurry to get into cold soil. Wait until the danger of frost has passed in your area before planting them directly in the garden.

If you want to get a head start on the season, you can "wake up" your cannas indoors about four to six weeks before the last frost. Plant the rhizomes in pots with potting soil and place them in a warm, sunny window. By the time the weather is warm enough to move them outside, you will already have established plants ready to grow. For a colorful starting point, Canna Tall Tropicanna Gold is a strong option to browse.

When planting, place the rhizomes about 4 to 5 inches deep. Position them horizontally in the soil with the "eyes" facing upward. Space them about 1 to 2 feet apart, depending on the variety’s mature size. Give them a good drink of water to settle the soil, and soon you will see those familiar pointed shoots breaking through the surface.

Conclusion

Storing canna bulbs indoors is a rewarding practice that connects the seasons and keeps your garden's history alive. It is a simple process of watching for the first frost, lifting the rhizomes with care, and providing a cool, dry place for them to rest. While it requires a small amount of effort in the fall, the payoff is a spectacular display of tropical color every summer without the need to start from scratch.

By paying attention to the moisture levels and temperature during the winter, you can ensure a high success rate. We hope this guide helps you feel confident in preserving your cannas. With a little bit of preparation and a few monthly check-ins, your garden will be ready to glow with vibrant canna blooms year after year.

• Wait for the first frost to trigger dormancy before digging.
• Cure the rhizomes in a dry, ventilated area for one week.
• Store in a cool, dark spot between 40°F and 55°F.
• Use a breathable medium like peat moss to maintain the right moisture balance.

"The secret to beautiful cannas every year is a little bit of patience in the fall and a cool, quiet place for them to rest during the winter."

To find more vibrant varieties and garden inspiration, feel free to explore our selection at Longfield Gardens. Happy gardening!

FAQ

Can I store canna rhizomes in the refrigerator?

While a refrigerator is cool and dark, it is generally not recommended for canna storage. Refrigerators are often too cold (usually around 35°F to 38°F) and the air is very dry, which can cause the rhizomes to shrivel quickly. Additionally, some fruits and vegetables in the fridge release ethylene gas, which can damage the dormant flower buds inside the rhizome.

Do I have to wash the soil off the rhizomes before storing?

It is not strictly necessary to wash them, and in many cases, it is better not to. If your soil is loose, simply shaking off the excess is enough. Washing is only recommended if the soil is heavy clay that won't come off easily, as thick mud can trap too much moisture against the rhizome during storage. If you do wash them, ensure they are completely dry before packing them away. For related seasonal care tips, the Garden Basics How To hub has plenty of practical guidance.

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

If the ground has frozen deep enough to reach the rhizomes, they may turn mushy and rot. However, if it was only a night or two of hard frost and the soil didn't freeze solid, they might still be fine. Dig them up immediately, inspect them for soft or translucent areas, and if they still feel firm, proceed with the curing and storage process. If you ever need help with an order question, the About Us page explains Longfield Gardens' 100% guarantee.

Why did my stored cannas grow mold during the winter?

Mold is usually a sign of either too much moisture or poor air circulation. If the rhizomes were not cured long enough, or if the storage container was airtight, humidity builds up and encourages fungal growth. To prevent this, ensure the rhizomes are dry to the touch before storing and use a breathable container like a cardboard box or a plastic bin with plenty of ventilation holes. If you are ordering more plants for spring, Shipping Information explains how Longfield Gardens schedules shipments by zone.