I've had Cannas in the ground for years and they always get the rust. There's little I've tried that had any effect. Just cut them back and let them regrow. Not a plant you grow for foliage anyhow, just flowers.

I'm just worried about what they're going to look like when it actually starts to rain! We've had such a dry winter & spring, that I find it hard to believe the soil is "too wet".

"Not a plant you grow for foliage anyhow, just flowers."

You may be right, but I kinda like the foliage.

Lou

I like the foliage too Lou!

I got this off the IFAS web site

The most troublesome pests of cannas are caterpillars, particularly leaf rollers, and
snails. Apart from occasional problems with bacterial leaf spot, diseases aren�t
usually significant where plants are grown in full sun and soil that isn�t too heavy.
Rust can sometimes affect foliage during periods of dry, cool (below 80�F) weather.

I'd love to know what helps too. Tried some of the low impact ideas over the last 2 years. Sprinkle corn meal, spray with milk water. Sprayed with both copper and sulphur based fungicides. No good. None worked. The disease seems to start midway through summer for me (about the time we start getting daily rains) and get steadily worse.

Reducing the clump size and making sure there is good circulation around it helps some. But basically I have resorted to cutting out infected plants at first. Once they are all infected I ignore the rust until they are too ugly too look at, then mow them to the ground. Not really the best solution. Would love to know a better way, or if there are resistant varieties. I have tropicanna and pretoria. Both are highly suceptible.

And I do grow them for the foliage, which I love. Which one is that with the white/green leaves Lou? That is beautiful!

SunWorshiper,
It's a canna that was discovered in a botanical garden in Germany.

This canna can grow to over 8 feet tall. The white part has a tendency to burn in full sun, so it's best grown in dappled shade like with banana trees around it.

Lou

I only grow canna for foilage. I don't think the flowers are all that pretty.

I love your Stuttgart canna, Lou.
Have you ever tried growing it in a pond? I heard some people have had success with it in ponds...
I had a Stuttgart last year that I was growing in afternoon shade/morning sun and doing well but then some type of worms got into the tuber and ate it gggrrrr. I will have to get another one off ebay. They really brighten up those shady corners.

SJN,
I keep buying more because they are so lovely in the garden setting. Seems I can't wait for them to multiply on their own :-)

I've always enjoyed variegated leafed plants and search for them on line.

Hush your mouth on those tuber eating worms, I'd go ballistic if that happened here :-(

I'm high on a hill and have no real low lying pond area on the ten acres unless I dig out a low spot and put in a pond liner. That notion has come up many times in my mind and one day I just may do it when I get an attack of senility.

Lou

bayer 3-1 for roses...no rust last year on the plumeria..first time in years....! it works...........

Bayer 3-1....what is it? Aspirin?

Bayer make s a host of plant products, We have a plant(the factory kind) in Vero

Thanks for the additional pictures Lou! That is so gorgeous! I'll have to keep a look out for those. Would they grow in full shade? The only spot I have any room left in my yard is on the north side of the house which is in shade about 80% of the day.

Thanks for the info on Bayer 3-1. I should have mentioned though that my cannas are intermixed among edibles. So I don't want to use anything that isn't food safe on them. I looked up the MSDS page (link below for the curious). It is more toxic than I'm willing to use. To be fair though, it is being targeted at ornamentals only.

So I'll have to keep searching for something that is food safe. Anyone have any luck with a control that is food safe?

Here is a link that might be useful: Bayer 3-in-1 MSDS

Sun worshiper,
In full shade they wont blanch out with the white and just be green like all the other cannas, too much sun and the leaves will scald/burn.

Lou

Thanks Lou. Good to know. I'll have to think about whether or not I have a spot where they'd be happy.