Are Tropical Orchids Epiphytes?

Epiphyte Facts

• In the home or garden, the biggest difference between tropical orchids and terrestrial orchids is that tropical orchids are epiphytes that have aerial roots. Instead of growing in dirt, they grow on tree branches with their roots exposed, absorbing water from the humid air around them. Some have pseudobulbs that store water. Examples of epiphytic orchids include the Cattleya, Dendrobium and Phalaenopsis; some orchids, such as the Oncidium, come in epiphytic and terrestrial varieties.

Tropical Orchid Potting Materials

• Because tropical orchid roots need lots of aeration, they need chunky potting materials that allow good air flow and mimic the materials in their natural habitats. Smart choices include fir tree bark chips, sphagnum moss, peat moss, perlite or a mixture of these. Water once or twice a week to keep the materials moist, but not waterlogged, increasing humidity for your orchid so its roots can absorb water.

Planting Orchids as Epiphytes

• If you want to closely mimic a tropical orchid's natural epiphytic habitat, you can create a jungle environment for it. Using cotton string that biodegrades, snugly tie orchid roots to a tree branch in your backyard or a hanging cork slab. The safest time to do this is when orchid roots are actively growing, which is typically in warm months between spring and early autumn. Over the course of several months, the orchid roots will naturally attach themselves to the tree, while the cotton string gradually deteriorates.

Creating an Epiphytic Habitat

• Whether you're planting an orchid in a pot for the windowsill or on a tree branch in your outdoor garden, you need to make sure the environment you create for your tropical plant supports their epiphytic nature. The most important feature is humidity, which should remain between 40 to 60 percent. An easy way to increase humidity, besides daily misting, is to place an orchid container on a tray filled with moist pebbles. Other environment necessities include weekly watering, fertilizer once a week to once a month and bright, indirect sunlight.