Growing Canna Lilies
Canna Lilies are not Lilies!
These fabulous wildly exotic plants are kissing cousins to Bananas and Ginger plants.
Order: Zingiberales, Family: Cannaceae, Genus: Canna
Although Canna Lilies originally came from the tropics, most of the cultivars have been developed in temperate areas. They will survive a wide range of conditions but I don't know of any that will live through the winter.
Canna Lilies have many uses
Canna Lilies are multi-talented plants. They have been grown for their spectacular foliage which can be various shades of green, variegated or a fabulous bronze colour. If you plant them in a shady area you will be unlikely to get many flowers but the fabulous foliage fills many otherwise empty space.
Most Canna Lilies have lovely flowers and produce seeds. In my garden growing canna lilies provide me with exuberant exotic foliage with the addition of bright red flower spikes. The flowers actually come in a wide range of colours and textures. The leaves can be green or bronze, variegated white and green, and I've even seen one plant with pinkish leaves.
Do you need a short term privacy hedge? Canna lilies can grow to 6 or more feet in a season and provide lots of temporary privacy while your real hedge is growing. Not only do they grow quickly but they can be planted in quite shallow soil, as long as you feed them and water them enough.
Cannas are not only grown for their appearance, but also for their large starchy rhizomes.
These are used for human and animal food. The foliage is useful as fodder and the young shoots are eaten when they are tender. The inner core is crispy and mildly sweet and can be added to salads (I've tasted them and give them thumbs up.)
The hard seeds have been used as beads and inside rattles. They are also ground into tortillas but I've not tasted these.
Canna plants have also been used to produce paper.
I planted quite a lot of cannas this year at my new house and the flowers were attracting lots of hummingbirds.
Growing Canna Lilies
Canna Lilies are a favourite of gardeners everywhere because of their good nature and reliable show. They are also safe around pets and children since they are not poisonous at all.
Given proper drainage they will thrive in most soils although I've had more success in lighter mixes. They don't like wet feet. They can tolerate dry conditions better.
Cannas are fast growing plants and can reach 6 feet in good conditions.
Cannas are usually grown from tubers or root division. In the fall I dig up enough roots to plant in the spring and put them away carefully. Here is a link to my page on overwintering canna lilies.
It's now mid April and it's time to start the cannas. I've found some of my storage roots and and cleaned up a good large clump. I then cut it in convenient sizes cutting out any rotten piece. You want a couple of eyes on each piece if you can. That clump gave me enough chunks to plant 5 small pots. It's good to let the cut dry in the sun for a short while, it helps prevent mold. I had a bit of rot this year because my tubers did not get a good chance to dry out before being put away. Fall was a hectic time and putting the canna roots away was low on the list.
I plant cannas in small pots 8-12 inches for the plants I just want to get started early before putting them in the ground, and plant in larger pots for cannas that I want to grow in pots. They make a nice potted plant but need a lot of water.
The smaller varieties are less likely to outgrow their pots as the larger ones. They can break their pot if they get too root bound. This pot cracked under the pressure.
One advantage of growing in large pots is that come fall, you can let the plant dry out a bit cut the tops off and store them, pot and all. In the spring you will have to re pot the divided roots but if you're in a hurry or the weather has been really too bad to dig up and dry the roots properly, you can store the pot with all the roots.
If you put the plants in a warm spot, I'm lucky, my pool enclosure is a plastic greenhouse, the plants will start coming up in a couple of weeks, depending on temperature of course. At this stage they don't need light so you could put them in a warm basement or shed until the shoots come up. They will then need to be kept in good light and not be allowed to freeze. You can see some shoots coming up in the larger pots.
When there is no more frost I'll plant them out.
You can wait till the chance of frost is past and plant your rhizomes directly in the ground. It will take a bit longer to get flowers though.
Canna lilies quickly grow into an attractive central plant. Here they anchor a new flowerbed before the more permanent plants have grown to size.
Garden store will often sell the young plants in the spring, looking innocent in smallish pots. As soon as you give them a bit more space they take off and grow at a surprising rate in good conditions. The Variegated types are slower. There are also "dwarf" varieties.
Canna lilies do very well in pots. I've grown them for years in my little Toronto back garden using 12-14 pots.
Plastic pots are better, Cannas can shatter a clay pot if the rhizome grow too big. I also have them in large garbage cans and they love this.
Canna Lilies like several hours of sun if they can get it. They will survive surprising amount of shade but flowers will not be as numerous. Plants on the left survive in mostly bright shade and camouflage the composter. Cats are often sleeping around the plant keeping an eye open for mice.
In the fall I dig up the rhizomes, let them dry a bit, then pack them up in rubbermaid containers filled with peat moss. I put them in the cool basement for the winter. They survive just fine.
Growing Canna Lilies from Seeds
Canna lilies can easily be grown from seed. Collect mature seeds in the fall and let them dry. They don't need to be kept cold (stratification). In the spring you can start them inside and put them out when there is no more frost. Canna seeds are tough little blighters and will do much better if you sand off a bit of the hard coating. Sand on a plain area, till you can see the inside, but don't damage it. Soak your seed overnight and plant. They like a little bottom heat and if you have a germinating mat you will get a better and quicker rate of germination. Keep watered but not soaking wet. The seedlings will come up in a couple of weeks (sometimes more, don't give up). Baby canna lilies look very sweet and small but quickly grow into big strapping plants so don't let them fool you into putting them in areas where they will crowd out their neighbours.
Every year I find a few seedlings popping up in unexpected areas. Since the seeds are quite tough they can survive for a few years in the ground if it's quite dry.
Pests and Diseases
Canna Lilies are hardy plants and are wonderfully free from problems.
Canna Lilies are delicious to Canna Leaf Rollers. These are little butterflies called skipper butterflies that produce a caterpillar that will shred a Canna Lily. They roll up the leaf and eat them. If you see the leaves getting gummed up with silk, you can open it up and remove the caterpillar. The leaf then gets a cleaning.
Last year I found a few very fuzzy caterpillars on my Cannas. They looked like the either Saltmarsh or Woolybear caterpillars. Probably Woolly bear, there are lots around here. This was the first time I saw them. They seemed to only eat the underside of the leaf.
There are insecticides that can control these bugs. I try to avoid them and between picking out the big bad guys by hand and letting the good bugs deal with the little bad guys, I don't seem to have much trouble.
One day I had the visit from a few Japanese Beetles
I know gardeners everywhere despise them but they are very lovely insects with their bright copper bodies and iridescent head. They have little furry skirts of white hair tufts. I left them alone on their Canna and they ate a leaf to lace. One afternoon there was wild Japanese beetle romance and sex, then they disappeared. They are large insects and can be picked off by hand. This is what I do if there are more than just a couple.
A large infestation can strip a plant in a few hours so keep an eye out. After you've picked off the beetles, wash the leaves with a hose. Japanese beetles leave a pheromone that attracts their friends.
When you go to pick off the beetles put one hand under the beetle then try and catch them with the other hand. They often jump off the leaf when they are pursued. Hopefully they land in your hand. Squish them or put them in a jar of soapy water to drown them.
There are also some viruses which attack Canna lilies. I've never seen any. Here is the Wikipedia article on Canna Virus.
At the end of the season before big frosts occur, you can dig up the roots dry them a bit and store them in a cool frost free area for planting next spring. Before planting you can split the larger roots and get several plants going. Look for growing buds for each of the new pieces. Let the cut or snapped pieces dry a bit before planting.
Some cannas don't really make rhizomes but rather have thick roots. In that case carefully dig up the plant, remove some of the soil and trim any long root and keep in moist peat over the winter. If the plant was in a small enough pot, just stop watering a few days before, cut off the tops and bring into a cool dark space for the winter. Don't bring in sopping wet plants though, they will rot.
I try to be accurate and check my information, but mistakes happen.email me if you find mistakes, I'll fix them and we'll all benefit: Christine