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Planting, Growing, and Caring for Cannas
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My Cannas leaves have something eating holes in them. What can I use to avoid this that is not toxic?
Hi, Karen. Cannas are susceptible to canna leaf rollers, Japanese beetles, root-knot nematodes, slugs, snails, and spider mites, just to name a few. Since you are not sure exactly what is eating your plants leaves, try treating with neem oil. It can control many pesky pests.
A comment and a question. First there is a caterpillar, (leaf roller?) that rolls the leaves/prevents leaves from unrolling, which are detrimental to cannas and will make the plants really ugly, as they munch holes in the rolled-up leaves. I have never been able to avoid these, even though living in several places in the state.
The question is, "Is any part of the canna edible?"
Hi, Olinda. Canna tubers can be eaten raw or cooked.
I purchased grown Cannas in pots that had finished blooming, I want to plant these in my garden (in zone 10). Can I remove them from the container and place the plant directly in the grounds or separate the roots and plant then directly? Thanks for your advice, I look forward to a beautiful display.
Can I leave my canna lily in the pot they were planted or do they need lots of room for planting. ( Medium size pot)
Hi Shirley,
Canna lilies are tall plants with extensive root systems so they need large, sturdy containers—at least 18 inches in diameter per rhizome—to thrive. It is likely that your medium pot will not be sufficient enough for your plant to reach its full potential, so it would be best to upgrade to a larger container that can both support root system growth and reduce the chance that it will become top heavy and tip over as it matures.
Given that your plant is in the midst of its growing season, you will want to wait until it finishes blooming for the season and its foliage begins to die back before transplanting to a new container. When you do transplant, you will want to use fresh potting mix and follow the planting tips outlined above.
Hope this helps!
Hi Nan,
You should leave you canna plants in the container during the winter months. Depending on how low temperatures are expected to get, you can leave them outside or bring them indoors and place in a cool, dry location.
In the spring, you can then remove the rhizomes and plant them directly into the ground. Depending on the size of your rhizomes, you can also divide at this time. Just make sure each divided piece has at least one eye. If you chose not to divide, remember that cannas should be divided every 3 to 4 years.
When planting in the ground, give your cannas room to grow as the rhizomes will spread.
Really enjoyed your article on Cannas almost as much as I enjoy Cannas. I'm in Zone 7b near Richmond, VA. Here, the leaf rollers are absolutely prolific, and the moths that lay the eggs must love my gardens. When I'm more conscientious and had more time, spraying them with Neem Oil is helpful. However, I have enough Cannas in different beds to make that too time consuming.
I understand you should not cover Cannas in the ground with heavy mulch, which I did once and lost EVERY one of them. So I'm thinking a light cover of peat mulch on entire beds might be good. What is your opinion ?
Cannas are also good for cleaning up any contamination in the soil, be it pesticides, oil slicks, road runoff and more. The plants should then be dug out and thrown away at the end of the growing season to remove the contamination they sucked up.
Several universities (including U Cal) are researching canna's ability to clean up all sorts of pollution.
After a minor (3gal) oil spill at my house a few years ago, I used cannas to suck up the oil that had soaked into the soil. The next year the area was oil free and one of the best growing spots in my yard.