I divided my dusty miller once last fall after it flowered. I did so, because that's what I heard to keep it growing and growing. Although i had no idea which one was older and which one was newer growth, I planted them all anyway after dividing it. One of the division died, so obviously it was the old portion of the plant. How do you tell the old from the new?

The rest has been growing so well. They are starting to flower now. It's my impression to snip the flower off in order to keep the plant acting like perennial. I noticed from my short experience as a gardener that most annuals don't die, if they don't reproduce, with the right zones.

I also noticed that not only do the annuals do that, but also perennials do not die back if they don't flower and set seeds.

So..... If i keep snipping off the flowers, will I keep dusty miller from dying after one season, instead of divide them by not knowing which one to keep. Also, it's much easier to snip off the flowers.

thanks