Canna lilies are perennial flowers that grow from rhizomes. In mild weather they will keep their leaves and continue to grow stems all year. In cold weather they will die back over winter and sprout again in spring. If the rhizomes are protected from extreme cold they will survive well in the ground and grow back on their own.
In US hardiness zones 8-10 they can be left in the ground. If the weather gets below 50 degrees Fahrenheit (10 degrees Celsius) over winter it is best to dig the rhizomes up and store them in your garage.
This article will explore how to get your cannas to come back every year. This will cover how to safely keep them in the ground and when to dig them up and store them for winter.
How to keep canna lilies in the ground over winter
Canna lily stems will die back over fall and winter in climates that get cold over these months. To get your canna lily rhizomes to grow back in spring it is important to cut them back at the right time and protect the roots.
How to get cannas to grow back each year
There are 3 easy steps to protect canna lilies over winter so they will grow back strong with loads of flowers in the next season.
1. Let the stems die back as much as possible
To encourage canna lilies to grow back each year it is important to let them die back as much as possible in fall and winter. The leaves and stems will turn brown and the rhizomes will reabsorb the nutrients from the stems.
I like to cut my stems back when I start to see rust develop on the leaves. This start to happen usually around the middle of fall. I usually put the stems in our green bins rather than composting them at home to prevent spreading the rust to other plants.
2. Cut the stems back
Cut the stems back to around 5 inches from the soil level. Cut the stems on an angel so that water doesn’t sit on the cut. This will help to prevent fungus and bacteria from growing on the stems over the cooler months.
Use clean secateurs when cutting the stems off. This will prevent any bacteria spreading from other plants and infecting the canna lilies.
3. Surround the stems with mulch
To protect the stems and rhizomes in the soil over winter it is important to surround them with a thick layer of bark mulch. You can also use straw or sugar cane mulch to protect the roots in the soil. Avoid overwatering the rhizomes in winter so they don’t rot. Just keep the soil slightly moist.
If you follow these steps the rhizomes will wait and be ready to sprout in spring. They will send up new, healthy stems that will grow 2-3 flower head on each one. They can continue to grow new stems over the spring and summer.
How to dig up cannas for the winter
If you live in a cold climate then it is best to dig up the canna lilies and store them. Here are the easy steps to store canna lily rhizomes at home
1. Wait for the stems to die back
Wait for the canna lily stems to die back. The leaves and stems will turn brown and return the nutrients to the rhizomes. If you notice that rust is forming on the leaves, cut the stems back and put them in your green bin.
2. Cut the stems off
Cut the stems back with sharp, clean secateurs. Leave around 5 inches on the stem and cut them at an angle.
3. Dig the rhizomes up and let them dry off for 3-4 days
Dig the rhizomes up from the soil carefully with a garden fork. Shake off as much soil as possible. If there is a lot of soil on the rhizome then you can wash the soil of with a hose.
Place the rhizomes on a piece of newspaper in the garage or garden shed to allow them to dry out completely. This will prevent fungal growth on the rhizomes when they are stored.
4. Store them in coconut coir or bark chips
Place the rhizomes in a plastic pot filled with coconut coir or bark chips. Spray the chips with water to keep the rhizomes moist. You can also wrap them in moist newspaper or hessian.
5. Keep them moist and store them in a dark place
Spray the rhizomes with water every month or so to keep them moist. When the weather starts to warm up in spring bring them out and get the soil ready to plant. Dig through some aged compost and aged cow manure.
Dig the aged organic matter through the soil and raise it up slightly. Replant the rhizomes in the soil and water them in well. They will send up new stems within 2-3 weeks and can flower within 6-8 weeks.
Leaving cannas in pots over winter
Canna lilies can be left in their pots over winter. Cut the stems down when they turn brown in fall and move the pot to a protected spot. Place it near a masonry wall, in a protected spot under your verandah or in your garage. Keep the rhizome moist but avoid getting any water on the stem end.
Do canna lilies come back every year? | Summary
Canna lilies come back every year if they are cared for over winter. In mild climates the rhizomes can be left in the soil. Cut back any stems that have turned brown and the rhizomes will send up new ones. Dig up the rhizomes in fall if the weather is cold.
Rhizomes can be stored in your garage over winter. Just make sure they are kept moist and they can be replanted in spring.
Happy growing.
I am an accredited practicing dietitian, experienced gardener and a dedicated cook. I love writing and sharing my experience so you can learn from my successes and mistakes.