Genus Rosa Species x Cultivar 'Radtko' Double Knock Out® Patent pp# 16202 Common Name Double Knock OutÂ® Rose Zone 4 to 9 Habit Medium, rounded shrub. Moderate growth rate. Height 3 to 4 Feet Spread 3 to 4 Feet Foliage Deep mossy green with blue and maroon highlights. Deciduous. Flower 3", double blooms with 18-25 petals from spring until frost. Cherry red. Light, slightly spicy fragrance. Flower Color Red Culture Full sun. Category: Rose Click to share on Facebook (Opens in new window)Click to share on Twitter (Opens in new window)Click to share on Pinterest (Opens in new window)Click to share on Tumblr (Opens in new window) Description Disease resistant, very strong bloomer.