Table of Contents
- Introduction
- The Best Time to Remove Canna Bulbs
- Timing Based on Your Gardening Zone
- How to Safely Remove Canna Bulbs
- Cleaning and Curing Your Rhizomes
- Dividing Your Cannas
- Winter Storage Techniques
- Managing Container-Grown Cannas
- Why Quality Matters
- Conclusion
- FAQ
Introduction
There is nothing quite like the tropical flair that cannas bring to a summer landscape. At Longfield Gardens, we love how these easy-to-grow cannas provide months of color even during the peak heat of August. As the season winds down and the air turns crisp, it is time to think about preserving these beauties so you can enjoy them all over again next year.
Removing canna bulbs—technically known as rhizomes—at the right time is the secret to successful overwintering. While it might seem like a complex task, it is actually a straightforward part of the gardening cycle. This guide is for anyone who wants to save their favorite varieties and expand their garden for the following spring. For a fuller overview, see All About Cannas. We will walk you through the timing, the digging process, and the best ways to keep your plants healthy while they rest.
Understanding the specific environmental cues that tell you when to move your cannas ensures they have stored enough energy to produce stunning flowers next season.
The Best Time to Remove Canna Bulbs
Timing is the most important factor when it comes to lifting your cannas. If you dig them up too early, the rhizomes may not have stored enough nutrients to survive the winter. If you wait too long, a deep freeze could damage the plant’s crown. The goal is to find that perfect window in late autumn.
The First Frost Signal
For most gardeners, the most reliable sign that it is time to remove canna bulbs is the first "killing frost." A light frost will usually cause the edges of the leaves to turn brown or black. This is nature's way of telling the plant to go dormant.
When the foliage turns dark and begins to wilt after a cold night, the plant has officially finished its work for the year. At this point, the nutrients from the leaves have traveled down into the rhizome. This stored energy is what the plant uses to push out new growth in the spring. Once you see that blackened foliage, you can safely begin the digging process.
Watching the Foliage
If you live in an area where frost comes very late, you can also look at the general health of the foliage. As the days get shorter and temperatures drop, cannas will naturally start to yellow and look less vibrant. Even if a frost hasn't hit yet, you can choose to lift them once they have clearly stopped growing and the leaves are no longer attractive. However, waiting for that first frost is generally the easiest way to ensure the plant is fully dormant.
Avoiding the Deep Freeze
While a light surface frost is helpful, a deep freeze is a different story. You want to remove the rhizomes before the ground itself freezes solid. If the soil freezes several inches deep, it can turn the moisture inside the rhizome into ice, which causes the plant tissue to rupture and rot. Keep an eye on your local weather forecast once November arrives. If a period of sustained, freezing daytime temperatures is predicted, it is time to get your shovel and get to work.
Key Takeaway: The ideal time to lift cannas is shortly after the first frost has blackened the leaves but before the ground freezes hard for the winter.
Timing Based on Your Gardening Zone
Because the United States has such a wide range of climates, "late fall" means something different for a gardener in Maine than it does for someone in Georgia. Your USDA Hardiness Zone Map determines whether you even need to remove your cannas at all.
Zones 8 and Warmer
In these warmer regions, cannas are generally considered hardy. The ground rarely stays frozen long enough to damage the rhizomes. In these zones, you can simply cut the foliage back to the ground after it browns and leave the rhizomes in the place. A light layer of mulch can help protect the crowns from occasional cold snaps, but lifting them is usually unnecessary unless you want to divide them.
Zone 7
Zone 7 is often considered the "swing zone." In many years, cannas will survive the winter if they are planted in a protected spot, such as near a south-facing wall, and covered with 6 to 8 inches of mulch like straw or shredded leaves. However, if a particularly harsh winter occurs, you might lose them. Many gardeners in Zone 7 choose to lift their favorite or more expensive varieties just to be safe.
Zones 3 through 6
If you garden in these cooler climates, cannas will not survive the winter outdoors. To keep your plants from year to year, you must remove the bulbs from the ground and store them in a frost-free location. This typically happens between late September and early November, depending on your specific location.
How to Safely Remove Canna Bulbs
Once the timing is right, the physical process of removing the rhizomes is quite simple. Because cannas grow from thick, fleshy structures, they are relatively sturdy, but you still want to handle them with care to avoid bruising.
Step 1: Cut Back the Foliage
Before you start digging, use a pair of clean garden shears to cut the stalks down. Most gardeners find it easiest to leave about 2 to 4 inches of stem attached to the rhizome. This "handle" makes it easier to move the clumps around and helps you remember which way is up when it comes time to replant. Removing the heavy, wilted foliage first also makes the digging area much cleaner.
Step 2: Loosen the Soil
Cannas can grow quite large over a single season, and their root systems can spread wider than you might expect. To avoid slicing through a healthy rhizome, start digging about 6 to 12 inches away from the base of the stems.
Using a garden fork or a sturdy spade, gently loosen the soil all the way around the plant. Angle your tool underneath the clump and use a levering motion to lift the entire mass upward. If the clump is particularly large, you may need to lift it in sections, but try to keep as much of the root mass intact as possible during this initial stage.
Step 3: Lift and Shake
Once the clump is loose, lift it out of the garden bed. Gently shake it to remove the bulk of the garden soil. At this stage, you will see that the original "bulb" you planted in the spring has likely multiplied into a large cluster of interconnected rhizomes.
What to do next:
- Cut stalks to 2–4 inches.
- Dig a wide circle around the plant to avoid damage.
- Lift the entire clump gently.
- Shake off loose soil by hand.
Cleaning and Curing Your Rhizomes
After the rhizomes are out of the ground, they need a bit of preparation before they go into storage. This transition period is called "curing," and it is a vital step for preventing rot.
To Wash or Not to Wash?
There is some debate among gardeners about whether to wash canna bulbs. Removing all the soil with a hose allows you to clearly see the health of the rhizomes and check for any pests. However, it also introduces extra moisture.
If your soil is heavy clay, washing is often the best way to get them clean. If you have sandy or loose soil, simply brushing it off by hand is usually enough. If you do choose to wash them, make sure they are allowed to dry completely in a well-ventilated area before moving to the next step.
The Importance of Curing
Curing is the process of letting the outer skin of the rhizome dry and toughen up. This acts as a protective barrier against fungal issues during the winter. Place your cleaned rhizomes in a dry, frost-free area like a garage or a covered porch.
Let them air dry for several days—up to a week is usually sufficient. During this time, the cut ends of the stems will dry out and "callous" over. Avoid placing them in direct sunlight during this process, as you want them to dry slowly and naturally.
Inspecting for Health
As you prepare them for storage, take a moment to inspect each clump. Healthy canna rhizomes should feel firm, similar to a fresh potato. If you find any parts that are soft, mushy, or smell bad, use a clean knife to trim those sections away. Discard any rhizomes that appear completely shriveled or diseased. Keeping only the healthiest specimens ensures that you aren't inviting rot into your storage containers.
Dividing Your Cannas
One of the best things about cannas is how much they multiply. A single rhizome planted in May can easily become a dozen or more by October. Fall is an excellent time to divide these clumps, though you can also wait until spring.
If you choose to divide them now, look for natural "nodes" or "eyes"—the small, pointed bumps where new growth will emerge. Each division should have at least one or two healthy eyes and a decent piece of the fleshy rhizome attached. Using a sharp, serrated knife makes clean cuts that heal quickly. Many gardeners find that dividing in the fall saves storage space, as you aren't storing the older, less productive center of the original clump.
Winter Storage Techniques
Now that your cannas are removed, cleaned, and cured, they need a cozy place to sleep for the winter. For a deeper dive, see How to Store Canna Bulbs for Winter. The goal is to keep them dormant, which requires a cool and dark environment.
The Ideal Environment
The "Goldilocks" temperature for canna storage is between 40°F and 50°F. If the temperature is too cold (below freezing), the rhizomes will die. If it is too warm (above 60°F), they may try to start growing prematurely or dry out too quickly. Unheated basements, crawl spaces, or insulated garages are often the best spots.
Packing Materials
To prevent the rhizomes from drying out completely (desiccation), it helps to pack them in a moisture-regulating material. Popular choices include:
- Peat Moss: Excellent for holding just enough moisture.
- Vermiculite or Perlite: Lightweight and clean.
- Shredded Newspaper: A great budget-friendly option.
- Wood Shavings: Often sold as pet bedding, these work very well.
Place a layer of your chosen material in the bottom of a cardboard box or a plastic bin with air holes. Arrange the rhizomes so they aren't touching each other, then cover them with more material. If you use plastic bins, ensure there is plenty of ventilation to prevent moisture buildup, which leads to mold.
Monthly Check-ins
It is a good idea to peek at your stored cannas once a month. If they look shriveled and dry, give the packing material a very light mist of water. You don't want them wet—just slightly damp. If you notice any fuzzy mold or soft spots, remove the affected pieces immediately to keep the rest of the batch healthy.
"A little bit of attention during the winter goes a long way. Checking for moisture levels once a month is the best way to ensure your cannas arrive in spring ready to grow."
Managing Container-Grown Cannas
If you grow your cannas in large pots, you have a shortcut available. For more container-growing tips, see How to Grow Summer Bulbs in Containers. You don't necessarily need to remove the bulbs from the soil.
Once the first frost hits, cut the foliage back to the soil level as you would with garden plants. Instead of digging the rhizomes out, simply move the entire pot into a cool, dark, frost-free area like a basement. The dry soil in the pot acts as the packing material. Stop watering the pot entirely until spring. This "lazy" method works exceptionally well and saves a lot of labor, provided you have the space to store large containers.
Why Quality Matters
When you start with high-quality plants from a trusted source like Longfield Gardens, your cannas are more likely to thrive and produce large, healthy rhizomes that are easy to overwinter. A good place to start is Canna Assorted Collection. While weather and soil play a huge role in gardening success, starting with strong genetics gives you a significant advantage.
We stand behind our plants with a quality guarantee because we want your gardening experience to be as rewarding as possible. Whether you are a beginner or a seasoned pro, following these simple steps for removing and storing your bulbs will help you build a stunning collection of cannas over the years.
Conclusion
Removing canna bulbs is a rewarding autumn ritual that signals the end of a successful growing season. By waiting for the first frost and carefully curing your rhizomes, you protect your investment and ensure a vibrant display for the following year. Gardening is a journey of cycles, and the dormant season is just as important as the blooming season.
Next Steps for Success:
- Wait for the first frost to blacken foliage before digging.
- Cure rhizomes in a dry, cool spot for several days.
- Store in a cool (40–50°F) location using peat moss or newspaper.
- Check monthly for rot or excessive dryness.
The effort you put into storing your cannas now will be rewarded in late spring when you see those first green shoots poking through the soil, ready to bring tropical beauty back to your garden.
For more inspiration and to see our full selection of summer-blooming bulbs, we invite you to visit our website and explore Tall Cannas. We are here to help you grow your best garden yet.
FAQ
Can I remove canna bulbs before the first frost?
Yes, you can remove them earlier if you need to clear your garden beds or if a long period of cold, wet weather is expected. However, waiting for the first frost is ideal because it signals the plant to go into full dormancy and ensures the rhizome has stored the maximum amount of energy for next year's growth. If you want a ready-made mix for next spring, the Canna Assorted Mix - Bulk Offer is a convenient choice.
What happens if the ground freezes before I dig up my cannas?
A light surface freeze usually won't hurt the rhizomes, as the soil provides some insulation. However, if the ground freezes deep enough to reach the rhizomes, they will likely turn to mush and die. If you miss the window and the ground freezes, it is still worth digging them up to check; if they are still firm, they may have survived. If you need to replant a larger space, Canna Tall Tropicanna is a great option.
Should I divide my canna rhizomes in the fall or the spring?
You can do either! Dividing in the fall saves storage space and allows the cut ends to callous over during the winter. Dividing in the spring allows you to see exactly where the new "eyes" or growth points are emerging, which can make it easier to decide where to make your cuts. Both methods are effective. If you want to browse a bigger, bold-looking grouping, see Canna Tall Pretoria.
Do I need to water my canna bulbs while they are in storage?
Generally, no. You want them to remain dormant and relatively dry. However, if you check them mid-winter and they look extremely shriveled or feel brittle, you can lightly mist the packing material (like peat moss) with water. Avoid making the material wet, as excess moisture is the leading cause of rot during storage. For a different look next season, try Canna Tall Australia.