Updated 15 October 2026

Bwindi epiphytes orchids is one of Uganda’s outstanding natural or cultural attractions, drawing visitors in search of wildlife, scenery, and authentic African experiences. Epiphytes are plants that grow on other plants without feeding on them, and in Bwindi Impenetrable Forest they cover almost every large branch: cushions of moss and liverwort, trailing lichens, ferns and small orchids, all living in the canopy without ever touching the soil. They thrive in Bwindi because the forest sits between 1,160 and 2,607 m, where mist, cloud and rain keep the air damp all year.

Most gorilla trekkers walk straight beneath this hanging garden without noticing it. This guide explains what epiphytes are, which groups you will see, why they matter to the forest, and where to look for them on your trek.

Epiphytes and orchids: the sky gardens of Bwindi’s forest canopy

What an epiphyte is

The word comes from the Greek epi (upon) and phyton (plant). An epiphyte uses a tree only as a perch, to get closer to the light. Unlike a parasite such as mistletoe, it takes nothing from the tree’s sap. Its water comes from rain, mist and the water that runs down branches in a storm. Its nutrients come from dust, bird droppings and the dead leaves and bark that collect in forks and crevices.

The trade-off is that the plant has no soil to fall back on when the weather dries, so epiphytes depend on constant moisture. That is why they are so abundant in montane cloud forests like Bwindi and much scarcer in the dry savannah parks of Uganda.

Epiphyte communities build up in stages. Lichens and mosses are usually the first to colonise bare bark. As they grow, die and trap debris, they create a thin, spongy layer of organic matter. Ferns and orchids then root into that layer, and over decades a big branch can carry a mat several centimetres thick with its own community of insects, spiders and fungi.

Mosses, liverworts and lichens

The easiest epiphytes to see are the bryophytes, the mosses and liverworts. In the wetter, higher parts of Bwindi they sheath trunks and branches so completely that the bark disappears under green and golden-brown cushions. Run a finger over one after rain and it is soaked like a sponge.

Lichens add pale grey-green crusts and, on exposed ridges and the upper branches of old trees, hanging beard-like strands of “old man’s beard” (Usnea). Lichens are partnerships between a fungus and an alga, and many species are sensitive to air pollution, so their abundance in Bwindi reflects how clean the air is.

These mats are small ecosystems in their own right. Mites, springtails and insect larvae live inside them, and small birds such as warblers and white-eyes pick through them for food. If you have a birding guide with you, watch how often birds forage on mossy branches rather than in open air. Our birding guide for gorilla trekkers covers the species you are most likely to see.

Ferns in the canopy

Bwindi has more than 100 recorded fern species, from the tall tree ferns of the valley bottoms to small filmy ferns only a few cells thick that need constant humidity to survive. Many grow as epiphytes along mossy branches. Some form nests or rosettes of fronds that catch falling leaves, which rot down into compost the fern then roots into, so in effect it makes its own soil in the air. Others creep along branches on thick, scaly rhizomes, sending up rows of fronds that curl up in dry spells and unfurl again after rain.

Orchids

Orchids are the most sought-after epiphytes, but in Bwindi they rarely look like the showy orchids of a florist. Most are small, with flowers a few millimetres to a couple of centimetres across in green, cream, yellow or dull purple, and they are easy to mistake for leaves or moss until you look closely. Uganda has several hundred orchid species, and the moist forests of the Albertine Rift, which include Bwindi, are among the richest places for them in East Africa.

Two genera that are common in African montane forests give a feel for the variety. Bulbophyllum orchids grow in lines along branches, with swollen green pseudobulbs that store water. Many have strange small flowers that attract flies with scents of carrion or dung. Polystachya orchids carry sprays of tiny, often yellowish flowers and are among the epiphytes most often seen in flower at eye level along trails.

You may also notice silvery-white roots wrapped around a branch with no obvious plant attached. These are orchid roots covered in velamen, a spongy layer that soaks up water in seconds when it rains and turns green when wet.

Why epiphytes matter to the forest

Epiphyte mats are an important part of how a cloud forest handles water. They catch mist that would otherwise drift through the trees, absorb heavy rain and release it slowly over the following days. That helps keep Bwindi’s streams flowing in the drier months and reduces flooding downhill, which matters to the farms around the park that depend on water from the forest. When mats fall, they add nutrients to the forest floor. Mature trees carry the heaviest loads, so old forest is far richer in epiphytes than regrowth.

Epiphytes also link to the rest of the forest’s food web. Fig trees, which begin life as epiphytes themselves before strangling their hosts, feed many of the forest’s birds and primates. Read more in our guide to Bwindi’s fig trees. Higher up, the broad, spreading crowns of Hagenia trees are often heavy with moss, lichen and ferns.

Where and how to see them on a gorilla trek

You will see epiphytes in every sector, but the densest growth is at higher altitudes, where cloud sits on the forest for longer. Ruhija, on the eastern side of the park at around 2,300 m, and the upper slopes of Rushaga and Nkuringo in the south are especially good. In the lower, warmer Buhoma sector, epiphytes are fewer but still easy to find along streams. Our guide to Ruhija’s birding and forest covers the high-altitude sector in more detail.

The best moments to look are the stops on the way to the gorillas, when the group waits for the trackers to radio the family’s position. Look at the branches at head height and just above, at fallen limbs, which bring canopy epiphytes down to eye level, and at the trunks of big old trees. A pair of close-focusing binoculars helps with orchids higher up.

Do not pick or peel anything. Collecting plants is illegal in Uganda’s national parks, and mats that took decades to form do not grow back quickly. The best season for orchid flowers is generally during and just after the rains, but something is usually in flower year-round. To understand why Bwindi is so rich in plants, read our guide to Bwindi as a UNESCO World Heritage Site.

Frequently asked questions