- DIVISION: Magnoliophyta
- CLASS: Magnoliopsida
- ORDER: Rubiales
- FAMILY: Rubiaceae
- GENUS: Pentas
- SPECIES: lanceolata
Colorful pentas, also known as Egyptian starcluster or star flower, are one of the best choices to attract pollinators like butterflies and hummingbirds to your garden. These hardy plants bear clusters of star-shaped flowers in vivid hues of red, pink, purple, or white, and they thrive in full sun.
Pentas are native to grasslands of East Africa and Yemen. In their native areas, they can grow into shrubs reaching up to 6 feet (1.8 meters) tall and spreading out up to 6 feet (1.8 meters) wide. When planted in backyard gardens as annuals, or as perennials in warmer climates where there is no frost danger, pentas are typically about 1 to 2 feet (30 to 60 centimeters) tall, but they can grow larger, with up to 5-inch (13-centimeter) diameter clusters of flowers. Pentas also are popular for use as container plants that can be grown indoors year round.
The name pentas comes from the Greek word meaning a series of five, referring to the five-pointed star shape of the plant’s flower. The multiple branches of this sprawling plant have dark green foliage with elongated leaves, up to 4 inches (10 centimeters) in length, and clusters of star-shaped flowers at the tips of all growth points, from spring through fall.
Pentas are low-maintenance plants that are relatively easy to grow—in a garden flower bed or in pots on a patio, in a window box, or inside the house. Many varieties are available from nurseries, in an array of colors, and they are known for being hardy and disease resistant. Aphids and spider mites are their most common foe in the backyard garden, especially during summer.
Plant pentas in full sun (in locations with at least six hours of sun daily) in moist, well-drained soil. Clay-laden or alkaline soils should be amended with peat moss. Water pentas when their top two to four inches of soil becomes dry. Trim off dead, woody stems and deadhead old flowers to keep the plant producing new growth—and new flowers. If stems grow too tall or spread too much, they can be cut back without damaging the plant.
You can see pentas at the San Diego Zoo Safari Park each spring during Butterfly Jungle. Butterflies are especially attracted to these plants’ colorful clusters of flowers.