The Double Red Knock Out® Rose Tree (Rosa 'Radtko') is a popular, low-maintenance, grafted standard tree featuring a 3–4 ft. head of fragrant, cherry-red, double-petal blooms. It is highly disease-resistant (black spot, mildew), drought-tolerant, and blooms from spring to frost, making it ideal for container gardening or formal, upright landscape accents. 
Key Characteristics and Care
Bloom Color & Type: Vivid, deep cherry red with a full, "double" petal count (roughly 25+ petals per bloom).
Form: A small, single-stem "tree" (standard) with a bushy, rounded top.
Size: Generally 3–4 feet in height and width.
Hardiness: USDA Zones 5–11.
Light Needs: Full sun is best (6+ hours), but tolerates partial shade.
Maintenance: Self-cleaning (no deadheading required), but light pruning in early spring is recommended to maintain shape.
Watering: Drought-tolerant once established; water deeply 1-2 times a week during dry spells.