Canna lilies need deadheading regularly throughout the spring and summer growing season. They can grow up to 3 flower stems from each leaf stem if they are cut regularly. Wait until the flower have dropped off and the seed pods have begun to form. Snip the flower head just above the last seed pod. Seed pods will start to form at the base of the flower first.
Deadheading canna lilies regularly will help the flowers to keep growing. Cannas can continue to send up new flower stems all the way throughout the summer.
This article will explore how to deadhead canna lilies to keep them blooming for as long as possible. Canna lilies are easy care plants that benefit from regular pruning.
How to deadhead a canna lily
Deadheading canna lilies is essential if you want them to keep flowering throughout the spring and summer season. I had flowers in early spring all the way to fall using this method. This will give you 2-3 flower heads per stem and a beautiful display.
1. Use clean secateurs
It is important to always start with clean secateurs. This will help to avoid spreading fungal or bacterial diseases between plants in your garden. I like to clean my secateurs with eucalyptus oil but you can also use methylated spirits or even warm soapy water.
Clean the secateurs after you have finished deadheading as well. Wipe them down with some vegetable oil to prevent them from rusting in between pruning.
2. Snip the flower head off below the last seed pod
Once the flower has finished, the petals are turning brown and falling off or you see seed pods developing it is time to remove the flower. Trace the flower stem down to the base and trim it just below the last flower head or seed pod.
This will allow the stems to send up another flower head giving you multiple blooms. The plant will usually wait for the first flower head to die back before sending up another one. Removing the old flowers or deadheading the cannas will encourage the plant to put more energy into producing new flowers rather than seed pods.
3. Repeat this process when the next flower dies back
This process can be repeated again to encourage a third flower head to appear. Just wait for the second flower head to die back and trim it just below its last flower. This will allow room for another flower stem to grow from the one canna leaf stem.
How to keep cannas blooming
There are some easy tips to follow to encourage your cannas to keep blooming over spring and summer. These tips will give you loads of flowers and make the most of every canna stem. Flowers come in all sorts of colors but the most common are red. This year I am trialing a new yellow flowering canna with bright green leaves.
1. Deadhead the cannas every 2 weeks
Deadheading cannas regularly is essential to keep cannas blooming through all of spring and summer. Check the plant every 2 weeks to see if the flower head has finished. The flower heads will die back and seed pods will appear quickly.
It is great if you can trim the flower heads off before the seed pods appear. That way the plant will not waste energy on growing seeds but will focus on flowers.
2. Water the plant well
Regular water for canna lilies is essential to keep it producing flowers. If you live in a tropical or subtropical region you will usually get more rain over summer. This means that you might only need to top up the water every week or so.
If you are getting less rainfall then check the soil and water the plants once or twice per week. This will give you more flowers and keep cannas blooming for longer.
3. Feed with pelleted chicken manure in spring
When spring arrives and new shoots are appearing from your canna rhizomes it is time to feed them with pelleted chicken manure. This will help the plant to get the nutrients it needs to grow new stems and strong rhizomes to produce flowers.
I like to only feed my cannas once with a high nitrogen fertilizer like chicken manure otherwise too much nitrogen can cause excess leaf growth and less flowers.
4. Plant them in full sun
Planting cannas in full sun is essential to get the most flowers possible. You can dig up canna rhizomes in spring and move them if they are getting too much shade. Plant canna rhizomes in pots so you can move them into the sun over spring and summer and protect them from winter frosts.
5. Separate rhizomes every 2-3 year to give them more room
Giving canna lilies the space they need to grow is essential to keep cannas blooming all season. Over a period of 2-3 years the rhizomes can become cramped or pot bound if they are left in the same space. Lifting the rhizomes with a garden fork in spring and separating them is a great way to give them the space they need.
Replant the rhizomes so they have at least 10 inches between each one. This will give you strong stems which will produce great blooms.
6. Plant them in fresh potting soil or improved ground soil
Before replanting canna rhizomes improve the soil so they have good drainage. This will help to prevent root rot and slowing the growth of the cannas.
If you are growing cannas in pots, plant them in fresh potting soil every 2-3 years. This will make sure they get the nutrients and drainage they need. Over time potting soil can become hydrophobic as the organic matter breaks down.
Fresh potting soil will make sure the cannas get the moisture they need to support large stems and lots of flower heads.
7. Use flower promoting fertilizer
If your cannas are producing lots of leaves and no flowers by summer add some flower promoting fertilizer. This will decrease the nitrogen to phosphorus ratio which will trigger the plant to produce flowers and not leaves.
Do Cannas Need Deadheading? | Summary
Cannas will grow more flower heads if they are deadheaded regularly. Trim each flower head just below the last flower or seed pod to avoid removing the next flower stem. You should be able to get at least 2-3 flower heads from each stem if they are cared for.
Remove the flowers just before the seed pods appear to allow the plant to focus its energy on the next flower stem rather than producing seed.