wilkes

Cut them to the ground when frost has killed the leaves and yellowed them. Remove the cut leaves and rake around the area where the cannas were planted. Remove this rubbish so that larvae which have cocooned and fallen to the ground will be gotten away from newly emerging plants in the Spring. Safer soap spray and a light spray of diatometic powder will help the leaves some - but - the nature of the canna is that it makes one terrific salad for all types of insects, borers, worms, and beetles. If you truly like cannas then learn to develop a blind eye to the holes in the leaves (caused also by hail). You can take up the tubers and store them in a dry cellar if you wish--just depends on whether you want an insurance policy against prolonged hard freezing of the ground or if you wish to divide the tubers for replanting.

I'm not sure about the worms but as far as care goes if they are planted on the south side of your house you can just cut the dead tops off at the ground after frost kills them. They will come back every year and keep spreading. But if they are on the north side they can freeze out. I dig up things and store them in a box insulated with styrafoam in my building that are on the north side of my house because if it snows or we have an ice storm it sometimes can lay there for weeks. Hope this helps!

Someone gave me some small canna lilies earlier this year. They grew beautifully, spread and are very tall..probably 6 feet. The only problem is that I began to see holes in all the leaves. When I looked closely whitish/light yellow furry worms were on the leaves eating them. They still bloomed just recently, but they look horrible with the holes in all the leaves. My first question is what do I do with them? I'm not an avid gardener so I don't know a lot about plants. Will they die off for the winter and then come back next year? If they die do I cut off the dead? Also, what can I do to prevent them from being eaten by worms next year?