Blockbuster™ Blue Catharanthus

Blockbuster™ Blue is an upright F1 Madagascar periwinkle (*Catharanthus roseus*) with large blue blooms and a compact, well-branched form. Syngenta describes the Blockbuster series as early flowering and heat loving, with garden dimensions of 10–12 inches tall by 12–16 inches wide. ## Landscape use Use it in sunny annual beds, mass plantings, borders, or containers. Its blue blooms bring cool contrast through summer. The breeder lists a mature spread of 12–16 inches; leave room for branching without crowding nearby plants. Syngenta gives a 7b–12b hardiness range; in colder climates, Catharanthus is commonly grown as a warm-season annual. See the [Syngenta Flowers cultivar profile](https://www.syngentaflowers.com/ams/product/flower/70104729) for the product details. ## Siting and water Choose a warm, sunny location with well-drained soil. [University of Florida IFAS Extension](https://ask.ifas.ufl.edu/publication/fp112) explains that Catharanthus performs well in heat and can develop root rot in poorly drained or overwatered conditions. Water during establishment, then avoid persistently wet beds. ## Maintenance Plant after cool spring weather has passed and the soil has warmed. Water as needed during dry spells while allowing the soil surface to dry between irrigations. Remove spent flowers for appearance if desired; [NC State Extension](https://plants.ces.ncsu.edu/plants/catharanthus-roseus/common-name/annual-vinca/) notes that modern hybrids generally need neither pinching nor deadheading.