How to Grow Cannas Indoors in Winter for Success

Table of Contents

1. Introduction
2. Choosing Your Winter Method: Active Growth vs. Dormancy
3. Method 1: Growing Cannas as Active Houseplants
4. Method 2: Storing Dormant Rhizomes Indoors
5. Method 3: Container Dormancy
6. Managing Pests and Health Indoors
7. Dividing Cannas for More Plants
8. Transitioning Back to the Garden
9. Understanding Hardiness Zones
10. Simple Care for Lasting Beauty
11. Conclusion
12. FAQ

Introduction

The lush, tropical drama of canna lilies is often the highlight of the summer garden. With their massive, paddle-like leaves and vibrant blossoms in shades of red, orange, and yellow, they bring an exotic energy to any landscape. The good news is that this beauty does not have to end when the first frost arrives. Because cannas grow from thick, energy-storing stems called rhizomes, they are remarkably resilient and easy to bring indoors. For gardeners who want to explore more varieties, Longfield Gardens’ Tall Cannas collection is a good place to start.

At Longfield Gardens, we want every gardener to feel confident about keeping their favorite plants from year to year. Growing cannas indoors through the winter is a rewarding way to protect your investment and ensure an even bigger display next summer. Whether you want to keep them as active houseplants or store them in a dormant state, the process is simple and achievable for gardeners of all levels. If you are comparing different canna options, the Canna Assorted Collection offers another way to enjoy these tropical favorites.

This guide will walk you through the most effective methods for managing cannas during the colder months. We will cover how to transition them from the garden to the house and how to provide the right care to keep them healthy until spring. By following these straightforward steps, you can enjoy the presence of these tropical giants all year round.

Bringing cannas indoors during the winter is a simple way to preserve your favorite varieties and prepare for a spectacular garden next season.

Choosing Your Winter Method: Active Growth vs. Dormancy

Before you bring your cannas inside, it is helpful to decide how you want to manage them. There are two primary ways to grow cannas indoors in winter. The first is to keep them in active growth as houseplants. This requires a very bright spot, such as a sunroom or a south-facing window, and consistent care. The second method is to allow the plants to go dormant while keeping the rhizomes safe and dry inside your home.

Most gardeners find that a combination of these methods or focusing on dormancy is the most practical. Active growth is exciting because it keeps the greenery visible, but it does require more attention to watering and light. Dormancy, on the other hand, is a "set it and forget it" approach that works perfectly in basements or closets. Both methods are effective, and the choice usually depends on how much indoor space and light you have available. For a broader overview of canna care, you can also browse All About Cannas.

Method 1: Growing Cannas as Active Houseplants

If you have a bright, sunny spot in your home, you can keep your cannas growing throughout the winter. This is a wonderful way to maintain a tropical vibe indoors when the landscape outside is bare. Because cannas are heavy feeders and love sunlight, you will need to mimic their natural summer environment as closely as possible. If you are deciding where cannas fit into your garden plan, the Spring-Planted Summer-Blooming Bulbs section is a helpful starting point.

Providing Ample Light

Light is the most critical factor for an active indoor canna. In their natural habitat, these plants soak up six to eight hours of direct sun. Indoors, even a bright window may not provide enough intensity. Place your pots in the sunniest spot available, ideally a south-facing window. If the leaves start to stretch or look pale, it is a sign they need more light.

Many gardeners find success by using a simple LED grow light to supplement natural sunshine. You don't need a professional setup; a basic grow bulb in a standard lamp can provide the extra boost your cannas need to stay vibrant. Aim for about 12 to 14 hours of light per day if you are using supplemental lighting.

Watering and Humidity

Cannas are thirsty plants, but indoor conditions are different from the garden. Inside, the air is often drier due to heating systems, but the soil stays wet longer because there is less evaporation from wind and intense heat. The goal is to keep the soil consistently moist but never soggy.

Check the soil every few days by sticking your finger about an inch deep. If it feels dry, give the plant a thorough drink. To help the leaves stay lush in dry indoor air, you can place the pot on a tray filled with pebbles and a little water. As the water evaporates, it creates a small pocket of humidity around the foliage.

Temperature and Airflow

Cannas prefer warm temperatures, making them comfortable in a standard home environment. They do best when temperatures stay between 65°F and 75°F. Avoid placing them directly in front of drafty windows or near heating vents, as sudden temperature swings can stress the plant.

Good airflow is also important for indoor plants. Every once in a while, open a window for a few minutes on a mild day or run a small fan in the room. This helps prevent stagnant air, which can lead to minor issues like mold on the soil surface.

What to do next:

• Identify the brightest window in your home for your canna.
• Check your pots for drainage holes to prevent water from sitting at the bottom.
• Monitor the soil moisture twice a week to establish a routine.

Method 2: Storing Dormant Rhizomes Indoors

For many of us, indoor space is limited, and we may not have the perfect sunroom for a six-foot-tall plant. This is where the dormancy method shines. By storing the rhizomes in a cool, dark place, you can keep the plants alive without needing any light or regular watering.

Timing the Transition

The best time to start the process is after the first light frost of autumn. A light frost will usually turn the leaves brown or black, which is a signal to the plant that it is time to rest. Don't worry—the rhizomes underground are protected by the soil. Once the foliage has withered, you can begin the transition.

At Longfield Gardens, we suggest cutting the stalks back to about four inches above the soil line before you dig them up. This makes the plants much easier to handle and protects the "eyes" or growth points on the rhizomes.

Digging and Cleaning

Using a garden fork or a spade, gently lift the clump of rhizomes out of the ground. Cannas have shallow roots, so you don't need to dig very deep. Once the clump is out, shake off the excess soil. You can use your hands to gently remove the bulk of the dirt, but there is no need to scrub them perfectly clean.

If you are transitioning cannas that were already in containers, the process is even easier. You can either leave them in the pot and move the entire container to a cool basement, or you can remove the rhizomes from the soil to save space.

Curing the Rhizomes

Curing is a simple but vital step. It involves letting the rhizomes dry out slightly before they go into storage. This toughens the outer skin and helps prevent rot. Place your cleaned rhizomes on a tray or a piece of cardboard in a dry, shaded area for two or three days. If you want another season-by-season refresher, see How to Overwinter Canna Lily Bulbs.

Avoid leaving them in direct sunlight during this time, as you don't want to "cook" the tender tissue. A garage or a covered porch is an ideal spot for curing. Once the surface feels dry to the touch, they are ready for their winter nap.

Packing for Storage

The goal of storage is to keep the rhizomes cool and dry, but not so dry that they shrivel up completely. Many gardeners find that packing them in a breathable material works best.

• Peat Moss or Vermiculite: These materials hold just enough moisture to keep the rhizomes healthy.
• Paper Bags: For smaller quantities, a simple brown paper bag works well.
• Cardboard Boxes: A sturdy box filled with wood shavings or shredded newspaper is an excellent choice.

Place the rhizomes in your chosen container and cover them loosely with the packing material. Do not use airtight plastic containers, as these trap moisture and can cause the rhizomes to rot.

Finding the Perfect Spot

Your indoor storage spot should be dark, dry, and cool. Ideal temperatures for dormant cannas are between 40°F and 50°F. An unheated basement, a cool closet, or a crawl space are usually the best options. If the temperature stays above freezing but below 55°F, your cannas will stay dormant and happy until spring.

Curing your canna rhizomes for a few days before storage is the secret to keeping them firm and healthy until it is time to replant.

Method 3: Container Dormancy

If your cannas spent the summer in large decorative pots, you have the easiest option of all. You can simply bring the entire pot indoors. This is a great time-saver and works exceptionally well for smaller varieties or for gardeners who don't want to deal with digging and cleaning. If you are planning more container plantings, How to Grow Canna Bulbs in Containers is a useful companion guide.

Preparing the Pot

Once the frost has nipped the foliage, cut the stems down to the soil level as you would with garden-grown cannas. Instead of digging them out, let the soil dry out significantly. Stop watering the pot entirely about two weeks before you move it inside.

Indoor Placement

Move the pot to a cool, dark area like a garage or basement. Because the soil provides a natural layer of insulation, the rhizomes are very well-protected. You don't need to do anything else for the rest of the winter. Every month or so, you can check the soil; if it feels bone-dry and dusty, you can add a tiny splash of water just to keep the rhizomes from completely dehydrating. You aren't trying to make the plant grow—just keeping it alive.

Managing Pests and Health Indoors

Whether you are growing cannas as active plants or storing them, it is a good idea to keep an eye on their health. Indoor environments can sometimes invite small visitors like spider mites or fungus gnats. To learn more about seasonal care, Longfield Gardens’ How to Care for Canna Bulbs article offers a helpful overview.

For Active Plants

If you notice tiny webs or speckling on the leaves of your active indoor cannas, you may have spider mites. These thrive in dry indoor air. The easiest solution is to wipe the leaves down with a damp cloth or give the plant a gentle "shower" in the sink or bathtub. Increasing the humidity around the plant will also discourage mites from returning.

Fungus gnats sometimes appear if the soil stays too wet. If you see small flies hovering near the pot, let the soil dry out a bit more between waterings. You can also place a thin layer of sand on top of the soil to prevent gnats from laying eggs.

For Stored Rhizomes

Check your stored rhizomes once a month. This only takes a minute and ensures everything is going smoothly. If you see a rhizome that looks soft or mushy, simply remove it and throw it away so it doesn't affect the others. If the rhizomes look very shriveled, mist the packing material with a little bit of water to add a touch of moisture.

Dividing Cannas for More Plants

Winter is a wonderful time to think about the upcoming garden season. Cannas are vigorous growers, and a single rhizome planted in spring can turn into a large clump by autumn. When you have your rhizomes out for cleaning or before you replant them in spring, you can easily divide them.

To divide a canna, look for the "eyes"—these are the small, rounded bumps where new stems will emerge. Use a clean, sharp knife to cut the rhizome into sections. Each section should have at least two or three healthy eyes. Let the cut ends dry for a day before planting. For more timing and storage tips, How to Properly Store Canna Bulbs Over Winter is worth a look.

This is one of the most cost-effective ways to fill your garden with color, as one year’s plant can easily become three or four plants for the next season.

Transitioning Back to the Garden

As the days grow longer and the threat of frost passes, it is time to wake your cannas up. This transition should be gradual to ensure the plants stay strong and healthy.

Starting Early Indoors

If you want a head start on the blooming season, you can pot up your dormant rhizomes about four to six weeks before the last expected frost. Use a high-quality potting mix and place the pots in a warm, sunny window. By the time the weather is warm enough to move them outside, you will already have several inches of green growth.

Hardening Off

When the soil has warmed up and there is no more danger of frost, you can begin moving your plants outdoors. This process is called "hardening off." Start by placing the pots in a sheltered, shady spot for a few hours a day. Gradually increase their time outside and their exposure to direct sunlight over the course of a week. If you want broader planting and climate guidance, the Hardiness Zone Map is a useful reference.

This prevents the leaves from getting "sunburned" and helps the plant adjust to the wind and temperature changes of the outdoors. Once they are acclimated, you can plant them in their permanent garden beds or leave them in their decorative containers.

Spring Transition Steps:

• Check rhizomes for firmness and healthy "eyes."
• Pot them up indoors 4–6 weeks before the last frost for earlier blooms.
• Wait for soil temperatures to reach at least 60°F before planting outside.
• Gradually introduce indoor plants to outdoor sunlight over 7–10 days.

Understanding Hardiness Zones

While this guide focuses on bringing cannas indoors, it is helpful to know if it is necessary for your specific location. Cannas are tropical perennials, meaning they are only hardy in warm climates.

In USDA hardiness zones 8 through 11, cannas can usually stay in the ground all year round. In zone 7, they may survive with a thick layer of mulch for protection, though bringing them in is a safer bet. For those of us in zones 6 and colder, bringing them indoors is a requirement if we want to see them again next year. For more climate background, Know Your Growing Zone: Cold Hardiness and Heat Tolerance is a helpful follow-up.

At Longfield Gardens, we ship our bulbs and rhizomes based on your specific gardening zone to ensure you receive them at the perfect time for planting. Knowing your zone helps you plan exactly when to bring your plants in and when it is safe to move them back out. If you are timing an order, Shipping Information explains how Longfield schedules shipments by zone.

Simple Care for Lasting Beauty

The most important thing to remember about growing cannas indoors in winter is that these plants want to survive. They are designed to store energy and wait for the right conditions to flourish. Whether you choose to keep them growing on a windowsill or tucked away in a box of peat moss, your efforts will be rewarded with a spectacular show of foliage and flowers come summer.

Gardening is about the joy of watching things grow, and there is a special satisfaction in seeing a plant you cared for all winter burst into bloom in the July heat. With just a little bit of preparation in the fall and a watchful eye during the winter, your cannas will become a permanent and beloved part of your garden landscape. Longfield Gardens’ 100% Quality Guarantee adds extra peace of mind when you shop.

Conclusion

Growing cannas indoors during the winter is a straightforward process that pays off in beautiful, vibrant displays year after year. By choosing the method that best fits your home—whether it's maintaining active growth or storing dormant rhizomes—you can ensure your tropical favorites stay healthy and strong. At Longfield Gardens, we believe that gardening should be a rewarding and accessible experience for everyone. Taking the time to protect your cannas over the winter is an easy win that guarantees a more beautiful yard when spring returns.

"Preserving your garden's beauty through the winter is as simple as providing a safe, cool space for your plants to rest."

We encourage you to try overwintering your cannas this year. It is a wonderful way to learn more about the life cycle of your plants and to enjoy the satisfaction of a garden that grows better with every passing season. Happy gardening!

FAQ

Can I leave my cannas in their outdoor pots all winter?

If you live in a region where the ground freezes, you should move the pots into a protected indoor area like a garage or basement. While the soil provides some insulation, the container itself can freeze through, which may damage the rhizomes. Bringing the pot into an unheated but frost-free space will keep the rhizomes safe until spring.

Do indoor cannas need fertilizer during the winter?

If you are storing dormant rhizomes, they do not need any fertilizer. If you are growing cannas as active houseplants, you can stop or significantly reduce fertilizing during the winter months. Because the plants grow more slowly indoors, they don't require the same nutrient boost they need during the peak of summer. You can resume a regular feeding schedule once you move them back outside in the spring.

How do I know if my stored rhizomes have rotted?

Healthy rhizomes should feel firm, similar to a fresh ginger root or a potato. If you notice any spots that feel mushy, soft, or have a visible mold growth, those are signs of rot. Simply cut away the affected area with a clean knife until you reach healthy white tissue, or discard the entire rhizome if the damage is extensive.

Why are the leaves on my indoor canna turning yellow?

Yellowing leaves on an active indoor plant are often a sign of either too much water or not enough light. Ensure the pot has excellent drainage and that you are only watering when the top inch of soil feels dry. If the light levels are low, the plant may drop older leaves to conserve energy. Moving the plant to a brighter window or adding a supplemental grow light usually solves the problem.