Scientific: Pentas lanceolata
Common: star clusters
Family: Rubiaceae
Origin: Tropical Africa

Pronounciation: PEN-tas lan-ce-o-LA-ta

Hardiness zones
Sunset
All zones as annual, 23-24 as perennial
USDA All zones as annual, 11 as perennial.

Landscape Use: Summer annual bedding plant, edging, accent, and container plant.

Form & Character: Formal and festive, refined.

Growth Habit: Cold sensitive herbaceous perennial grown as annual in Phoenix area. Moderate growth rate to 2 feet maximum in our area.

Foliage/Texture: Ovate to lanceolate leaves with prominent pinnate patterns of venation, medium to dark green; medium texture.

Flowers & Fruits: Umbellate clusters of pink small, white, lilac or red flowers, each cluster to 4 inches in diameter; fruit inconspicuous.

Seasonal Color: Blooms all summer, but most heavily in May and June.

Temperature: Surprisingly heat loving, but intolerant of temperatures below 40oF.

Light: Full sun to partial shade

Soil: Provide star clusters a rich soil amended with organic matter (high water and nutrient holding capacity) that is well drained.

Watering: Star clusters requires frequent moderate amounts of water to grow in Phoenix during the summer.

Pruning: Remove dead or old flower clusters as they are born terminally and apically in umbellate clusters.

Propagation: Seed

Disease and pests: None, because star clusters is a short lived annual plant in Phoenix landscapes.

Additional comments: Star clusters is a decent summer annual for landscape flower beds and borders in mesic and oasis designs in the Phoenix area.  Its also a nice container pot plant and may also be used as a cut flower. Star clusters is not a good choice for arid or desert landscapes themes or unamended desert soils. There are many named cultivars of different flower colors including 'Butterfly Blush'.