Epidendrum aka Star Orchid

Water Epidendrum orchids every 4-5 days during the active growing season (spring through early fall), keeping the potting medium consistently moist but never soggy. As growth slows in late fall and winter, reduce watering to every 7-8 days, allowing the medium to dry slightly between waterings. A good general rule is to water once a week year-round, adjusting based on your home's temperature and humidity levels.

Epidendrum orchids require a well-draining orchid mix consisting of equal parts fine and medium-grade fir bark, with 15-20% coarse perlite added for additional drainage and aeration. Being epiphytic orchids, they need an open, chunky medium that allows air to circulate around the roots while retaining some moisture. Standard potting soil will suffocate the roots and cause rot.

Epidendrum orchids thrive in humidity levels of 50-80% year-round, with 60-70% being ideal. While their thick leaves enable them to tolerate somewhat drier air better than many orchids, they still benefit from regular misting of leaves and aerial roots if your home humidity falls below 50%. Good air circulation is essential at higher humidity levels to prevent fungal and bacterial issues.

Epidendrums prefer warm daytime temperatures of 20-30°C (68-86°F) and cooler nights of 15-20°C (59-68°F). They can tolerate temperatures as low as 10°C (50°F) but should be kept above 15°C (59°F) for optimal growth. This 5-10°C nighttime temperature drop is important for encouraging flowering. Avoid exposing plants to freezing temperatures, which will cause damage or death.

Feed Epidendrum orchids with a balanced fertilizer approximating 20-10-20 NPK ratio during the active growing season from spring through early fall. If using purified or distilled water, occasionally supplement with calcium. Significantly reduce or stop fertilizing by September-October to limit unwanted winter cane growth and encourage flowering. Follow the 'weakly, weekly' approach—dilute fertilizer to quarter or half strength and apply with each watering.

Epidendrums propagate easily through keikis (baby plants) that develop along the stems or from flower spikes. Wait until keikis have 3-4 roots at least 2-3 inches long, then cut them from the mother plant with sterile tools and pot in orchid bark. You can also divide mature plants by separating sections with 2-4 pseudobulbs each. Another method is cutting old canes into pieces with 1-2 nodes each and laying them on moist sphagnum moss until new growth appears.

Repot Epidendrum orchids every 2-3 years in spring or early summer when new growth and roots appear at the base. Interestingly, orchids actually prefer being pot-bound, so only repot when the potting medium has broken down significantly or the plant has completely outgrown its container. Use fresh orchid bark mix and a pot only slightly larger than the previous one. Roots growing on the surface are normal and a sign of a healthy plant.

Epidendrum is native to the Neotropics, spanning from the southern United States (Florida and North Carolina) through Mexico, Central America, and into South America including the Andes, Brazil, and Argentina. The genus shows highest diversity in the Andean countries of Colombia (610+ species), Ecuador, and Peru (400-500 species each). These orchids occupy diverse habitats from sea level to over 3,500 meters elevation in cloud forests and páramos.

Epidendrum orchids are prolific bloomers, with many species flowering nearly year-round in ideal conditions, though blooming typically peaks from late winter through spring. Reed-stem types are particularly known as 'constant flowering plants.' Flowers appear in terminal clusters and range from orange, red, and yellow to white and lavender, typically measuring 1-2cm across with narrow petals and a characteristic three-lobed lip. Individual blooms can last several weeks, with new flowers continuously opening on the same spike.

Popular cultivated Epidendrum species include E. ibaguense (Crucifix Orchid), known for nearly year-round blooming with flowers in lavender, red, orange, or yellow; E. radicans (Fire-Star Orchid), distinguished by roots along the stem length and red-orange flowers; E. cinnabarinum, with bright red blooms but less cold tolerance; E. secundum, blooming year-round; and E. nocturnum, fragrant at night. With over 1,500 species in the genus, many hybrids have been developed combining the best traits of these species.

The two most common pests affecting Epidendrums are hard brown scale and aphids. Scale insects create sticky honeydew that attracts ants and causes yellow patches on leaves, while aphids feed on tender new growth, stunting development and preventing flowering. Both can be controlled with 70% isopropyl alcohol on a swab for spot treatment, or insecticidal soap and horticultural oil sprays for larger infestations. Good air circulation helps prevent both pest problems and fungal issues. Always isolate affected plants during treatment.

Yellow leaves on Epidendrum typically indicate scale insect infestation, nutrient deficiencies, or watering problems. Check carefully for small brown bumps (scale) on leaves and stems—these sap-feeding insects create yellow patches. If no pests are visible, consider whether you're over or under-watering, or if the plant needs fertilizer during the growing season. Older lower leaves naturally yellow and drop as part of normal growth, which isn't cause for concern.

Epidendrum orchids exhibit a moderate growth rate, typically adding 12-24 inches per year under ideal conditions. Most species reach mature heights of 1-3 feet (30-90 cm), with reed-stem types like E. ibaguense potentially growing 3-5 feet tall. Plants spread 1-2 feet wide on average. They go through a 1-2 year vegetative growth phase before beginning to flower, usually reaching blooming maturity around 2-3 years from propagation. Growth pattern varies—some produce cane-like stems while others form clumps of pseudobulbs.

Epidendrums can be grown outdoors year-round in USDA hardiness zones 9-11, where temperatures remain above 50°F (10°C). Some growers in mild climates grow them outdoors to maximize light exposure. In cooler zones, treat them as container plants and bring indoors before frost. While some varieties like E. ibaguense can tolerate brief light frosts, prolonged exposure to freezing temperatures will damage or kill the plants. In suitable climates, they make spectacular displays in raised planter beds or large containers.