Most growers would say to wait until about a week after the first frost. That way, the plant will close its stems down, and start to produce eyes for replenishing itself.

That being said, I am often away at that time, so I dig mine before the optimum time. .... probably later this month.

Interestingly enough, this coming weekend the weather is predicted to go down to 4C. Could be frost.

I am in Ont also and our first front date according to Enviro Canada and the farmer's almanac is Sept 16 this year. So, maybe the first frost will be before this weekend.

Sheryl,

FWIW, I too am in Ontario in Lindsay. I generally dig mine up late October or early November. I let the frost hard kill the plant before I dig it up, unless there's a forecast for many inches of snow. If the flowers aren't getting mushy, why cut them down?

Cheers,
Russ

I'd like a lot of eyes to grow on it before I dig it up. I will leave it there until the frost kills it. We did have amild frost this weekend, enough to do in my tomatos but not the dahlia.