Rosa, Genus, 'Sunset Horizon', Cultivar,
- Genus
- Cultivar
Sunset Horizon Rose
Of garden origin; no wild distribution
Overview
Rosa 'Sunset Horizon' is an upright grandiflora-type rose that reaches 4-5 feet (1.2-1.5 m) tall and 2.5-3 feet (75-90 cm) wide on strong, branching canes. The semi-glossy dark green leaflets back large double flowers about 4 inches (10 cm) across, each carrying a warm blend of yellow, orange, and pink that deepens at the petal edges. The blend shifts with temperature and age, running more yellow in heat and richer orange-pink in cool weather, so no two flushes match exactly. A moderate fruity fragrance accompanies the bloom. Flowers open singly and in small clusters and repeat from early summer into autumn. Like most modern roses in this class, the plant needs full sun, steady feeding, and even moisture to hold its repeat bloom, and flowering slows in cool, overcast spells. In humid climates the foliage can develop black spot where air movement is poor. The canes are thorny, and in the colder part of the range winter dieback is cut away at spring pruning. Hardy in USDA zones 5-9, it tolerates summer heat with consistent root moisture. The long stems suit cutting.
Native Range
Rosa 'Sunset Horizon' is a hybrid of garden origin with no wild distribution. The genus Rosa is native to temperate and subtropical regions across the Northern Hemisphere.Suggested Uses
Grown in rose beds and mixed borders, and as a low flowering hedge spaced about 30 inches (75 cm) apart. The long, strong stems supply cut flowers. Plants also grow in containers of 7 gallons (26 L) or larger.How to Identify
Appearance
Size & Dimensions
Height4' - 5'
Width/Spread2'6" - 3'
Bloom Information
Bloom begins in early summer and recurs in flushes into autumn. Individual flowers last several days, and removing spent blooms encourages the next flush. Flower color leans more yellow in summer heat and deeper orange-pink as nights cool toward fall.
Detailed Descriptions
Flower Description
Yellow, orange, and pink blendFoliage Description
Semi-glossy dark greenGrowing Conditions
Sun Requirements
Requires 6-8 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Plant in full sun in deep, well-drained loam at a pH of 6.0-6.5. Water deeply once or twice weekly through the growing season, keeping foliage dry to limit black spot. Feed with a balanced rose fertilizer in early spring and after each flush. A 2-3 inch (5-8 cm) mulch layer conserves moisture and steadies root temperature. In zones 5-6, mound soil or mulch over the graft union before hard frost. Space plants about 30 inches (75 cm) apart to maintain airflow in humid climates.Pruning
Prune in early spring, shortening canes to 15-20 inches (38-50 cm) above outward-facing buds and clearing dead or thin wood. Remove the oldest canes at the base over several seasons to renew the bush. Deadhead through summer to a five-leaflet leaf to sustain repeat bloom.Pruning Schedule
Prune: March–April
early spring
Container Growing
Suitable for container growing
Minimum container size: 7 gallons
