At just over 20 years old, knockout roses are pretty new to ... Unfortunately, heirloom roses are more prone to disease and ...

Fact checked by Jillian Dara Roses, long a gardener's favorite and our country's National Flower, still suffer from the ...

And they've got good resistance to common rose diseases like black spot and powdery mildew so you don't have to constantly treat them to have them look good. While not every Knock Out rose has a ...