Canna lilies may be unrelated to true lilies, but they certainly compete for best display each year. You can easily divide your cannas after they reach a certain age.
This propagation method is perhaps the easiest and is only done every 3 or so years.
But what if you don’t want to wait that long to add to your canna collection? More on caring for canna lilies here.
The good news is that you can propagate canna lilies using seeds with minimal effort once you know a few tricks.
How To Grow Canna From Seed?
Most failures in propagating canna seeds come down to their hard shells.
The following guide will show you how to get around this problem and enjoy a high success rate.
First of all, this step is the cause of almost all failures for canna seeds, so it should be considered the most important.
This step is also easy to get right once you know what tends to go wrong.
Canna lilies have developed a hard shell around their seeds to protect them from environmental conditions.
The seed responds to set stimuli which weakens the shell and enables germination.
Think of it like how pine cones require extreme heat to release their seeds.
This brings up the second point: Canna seeds need to be chipped or scratched to emulate nature’s process.
Unfortunately, many failures occur because growers accidentally damage the embryo while chipping it.
Because these seeds are about the size and shape of ball bearings, pick a spot where they’re less likely to ping out of reach.
Working with a large cardboard box on its side can reduce the areas where seeds can escape.
Also, sit in a corner so that any ricochet will fall in or near that corner.
Next, make sure you have the right tools for the job.
A pair of infant fingernail clippers will work wonders because the protective plastic shell won’t let you cut deep enough to cause damage.
Holding the seed carefully, angle in your clippers, and create a scratch in the side of the seed.
Setting the seeds on a piece of duct tape can significantly reduce the risk of runaways or self-injury.
Another option is using a razor blade to scratch the seed until you see a touch of the white layer under the shell coating.
Don’t worry if you accidentally damage one or two seeds when you first start.
Getting the pressure right can take a little practice, but there are plenty of seeds to make up for one or two failures.
Now that you’ve nicked them, it’s time to soak the seeds to wake them up.
If you’ve used duct tape to keep them from straying, this process will also help remove the resulting stickiness.
Use a small bowl to hold the seeds and some natural rainwater or distilled water.
Add the water until it covers the seeds 1″ to 2″ inches.
Let them soak for 5 days, changing the water out daily.
While the seeds are soaking, get your planting containers ready.
Use germination flats or other containers as long as they have drainage holes. Most growers like to use small seedling pots.
These are small enough to hold 1 to 2 seeds each and make it easy to transplant them later.
Note that seed trays can somewhat reduce the germination success rate, hence why small pots tend to be the most popular choice.
You can use several different mediums for germination.
Some prefer soilless commercial mixes, others straight vermiculite.
Fresh multi-purpose compost is a great way to give canna seeds a head start.
Pour some boiling water over the potting compost about an hour before sowing. A small, fine-nozzled watering can work great in reducing burn risks.
The wet soil will cool off in that hour but still leave the compost warm and cozy.
Place each seed on the surface of your potting material and gently press it in, so no more than a ¼” inch of medium covers them.
If you didn’t add water beforehand, now’s the time to get the potting medium nice and moist (but not wet).
Cover the containers with gallon freezer bags to improve humidity. Place them in a spot where the temperature remains between 65° and 75° degrees Fahrenheit during the day and 60° to 70° degrees Fahrenheit at night.
Be careful not to expose the pots to direct sunlight, speed up evaporation and dry out the pots.
Add a little water every 1 to 2 days (misting the soil also works).
It usually takes about 1 to 2 weeks for the seeds to germinate.
Cannas are monocots, so you’ll only see one leaf at first.
Remove your humidity tent once the seedling has sprouted and place the container in a sunny window.
Be sure to rotate the container occasionally so the plant won’t grow crooked.
You’ll want the seedlings to reach 6″ inches in height before transplanting.
It’s finally time to introduce your little cannas to their permanent home.
For plants intended for the garden, bring them out for an hour once frost has passed.
Keep them shaded, as they’re not acclimated to direct sunlight.
Continue taking them outside for an hour longer each day, moving them further into direct light each time.
This practice will get the seedlings used to the outside environment.
Soak the pots for indoor and outdoor-bound plants to loosen up whatever medium you use, then gently pull the plants out.
You can skip this step if the seedlings have their own 2″ to 3″ inch pots or do so to replace the medium.
If you grew multiple plants in one container, you might need to tease their roots apart gently.
Finally, give each indoor plant its own small container.
Avoid going too big, as this can stress cannas. They like a little company.