Houseplants
Hoya, Genus, carnosa, Species,
- Genus & species
Wax plant
Southern China, Taiwan, the Ryukyu Islands, Vietnam, and northeastern Australia
Overview
Hoya carnosa is an evergreen, twining vine in the dogbane family (Apocynaceae), with woody-based stems that climb to 10–20 feet (3–6 m) outdoors and are commonly kept at 3–6 feet (0.9–1.8 m) indoors on a trellis or hoop. Leaves are opposite, thick and fleshy, ovate to elliptic, 2–4 inches (5–10 cm) long and 1–2 inches (2.5–5 cm) wide, glossy green with a waxy surface, and sometimes lightly flecked with silver. Stems exude a sticky white latex when cut and produce aerial roots at the nodes that attach to supports. Flowers are held in rounded umbels of 10–30 on persistent, leafless stalks (peduncles). Each flower is 0.4–0.5 inch (10–12 mm) across, star-shaped, and made of a waxy white to pale pink corolla topped by a smaller five-pointed corona that is pink to deep red at the center. Flowers are fragrant, most strongly in the evening, and drip clear nectar. Growth is slow, at 6–12 inches (15–30 cm) per year indoors. The species is frost-tender and is damaged by temperatures below 50°F (10°C). Plants may take 2–5 years from cutting to first flowering, and overwatering is the main cause of root rot.
Native Range
Hoya carnosa is native to southern China, Taiwan, the Ryukyu Islands of Japan, Vietnam, and northeastern Australia. It grows as an epiphyte in tropical and subtropical forests, climbing tree trunks and rock faces in bright, filtered light.Suggested Uses
Grown as a houseplant in hanging baskets, on trellises, and along window frames. Grown outdoors in zones 10–12 on walls and fences in partial shade. Mature plants flower under bright indoor light at 60–85°F (16–29°C).How to Identify
Appearance
Size & Dimensions
Height3' - 20'
Width/Spread1' - 3'
Bloom Information
Detailed Descriptions
Flower Description
White to pale pink with a red centerFoliage Description
Glossy green, sometimes silver-fleckedGrowing Conditions
Sun Requirements
Requires 4-6 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
Grows in bright, indirect light, 4–6 hours of filtered sun, with brief morning sun tolerated by mature plants. Potting mix is chunky and fast-draining, such as bark and perlite blended with potting soil, with a pH of 6.0–7.0. The top 1–2 inches (2.5–5 cm) of mix is allowed to dry between waterings, typically every 7–14 days in warm months and every 3–4 weeks in winter. Typical growing temperatures are 60–85°F (16–29°C), and USDA zones 10–12 allow outdoor growth. Pots of 4–6 inches (10–15 cm) are used because plants flower when slightly root-bound. Mealybugs collect at leaf axils and are a common pest.Pruning
Stems are trimmed only to remove dead tissue or to shorten stems that exceed their support. Flower stalks (peduncles) persist and rebloom from the same spurs in later seasons, so cutting them removes future bloom sites. Cuttings of 4–6 inches (10–15 cm) with 2–3 nodes root in water or moist mix in 3–6 weeks.Pruning Schedule
Prune: March–April
early spring
Container Growing
Suitable for container growing
Minimum container size: 1 gallons
