Canna damage

Friday, August 20, 2010


Canna damage
Originally uploaded by sassycrafter
The other day, I noticed a lot of damage on this canna. I figured I'd better take a look at the plant and see what was going on. After a brief scouting session, I found a hungry larger canna leaf roller that was treating my beloved canna like his own personal all-you-can-eat buffet. This was definitely not cool in my book, since this was the Canna 'Intrigue' that I paid good money for on my trip to Plant Delights Nursery.

If you live in Florida and don't know about canna leaf rollers, then it's time you learned. Most of the people I work with here at UF/IFAS would probably agree that leaf rollers are the most troublesome canna pests in our state. In fact, all of the damage that I found on my plant seemed to be the result of a single critter. Sure, it took me a few days between when I noticed the problem and when I checked it out. But still -- that's a lot of damage for just one caterpillar.
Larger canna leaf roller (UF/IFAS)

The lesser canna leaf roller can be a little harder to discover. These caterpillars are much smaller and typically roll themselves up in the edge of a leaf, where they then feed only on the top layer of the leaf.

Lesser canna leaf roller (UF/IFAS)
So if you have cannas in your yard, be sure to scout for pests often. It's a snap to make your own scouting kit, and it's much easier to get a problem under control if you find it early. You can hand pick the pests if there's just a few of them, or treat the plant with a biorational insecticide like Bt (Bacillus thuringiensis) that kills the caterpillars without harming beneficial insects.

Needless to say, that leaf roller won't be bothering my plants again.

5 comments:

Steve Asbell said...

Thanks for the info! My canna indica that I started from seed mysteriously turned yellow and died earlier this summer. Any idea why?

Kim Taylor Kruse said...

Don't you just hate when plants do that? The ensete I planted this year had similar problems. It's hard to say what causes issues like this.

Kimberly said...

Great info! I don't have any, that I know of, and I have a lot of cannas! I'll be on the look out!

LiveToGarden.com said...

I'm going to be very mindful of this problem! Thanks for highlighting it!

Beautiful Gardens said...

Truly astonishing. Good job you got rid of them, and on the public service announcement ;)