T he orchid family Orchidaceae is a huge group that features epiphytic, lithophytic and terrestrial members. Although most orchids won’t grow from cuttings, some members of the Dendrobium genus will produce new plants from stem cuttings. The Noble Dendrobium (Dendrobium nobile) is one such species. Grown as a houseplant, it provides an impressive display of flowers from late winter to early summer.

Dendrobium Nobile Flowers

The Noble Dendrobium produces single blossoms or groups of flowers on short spikes that emerge from the nodes along the stem or pseudobulb. After the flowers fade, you can clip the spikes with scissors or shears. Dip the blades of your cutting tool in rubbing alcohol between cuts to help prevent the spread of infection.

Stem Cutting

After the flowers die back, select one or more stems of up to one foot long. Snip them off the parent plant and cut into sections with three to four nodes each. Set the cuttings aside.

Rooting Tray

Prepare a rooting tray with a layer of pebbles, sphagnum moss or bark. Soak the moss or bark in water until completely wet; then allow the water to drain from the medium. Spread the medium in an even layer in the tray. Place the stem cuttings on top of the medium and mist with water. Cover the tray loosely with plastic wrap to keep the humidity high. Put the tray in a warm, dark location.

Cutting Care

Keep the rooting tray at a temperature of between 75 to 85°F. A seedling heat mat can help maintain a consistent temperature. Mist the cuttings regularly to keep them moist, but not waterlogged. Every two weeks for the first two months, mist with a water-soluble nitrogen fertiliser or liquid seaweed extract, followed by a light misting of water. You can also spritz the cuttings with a 6-6-8 foliar fertiliser in alternate weeks. Continue to use the foliar fertiliser every two weeks until the cuttings develop leaves and roots. Discard any cuttings that show signs of rotting.

Potting Basics

After the cuttings develop new shoots and roots, gently cut the stem between the plantlets using sterilised anvil pruners. These baby plants are also called keikis when they develop naturally on the pseudobulbs or stems of the parent plant.

Dendrobiums prefer small flowerpots. Pot the new plants in 2-inch pots using a loose orchid medium of bark, weathered volcanic rock or sphagnum moss. Soak the medium first to ensure it is completely moist. Plant the new plantlet with the old stem standing upright and the shoots facing to the side or upward. Gently tuck the plant into the medium and add a stake if necessary to hold it upright and in position. The new leaves will grow up, and the roots will wind their way through the potting medium.

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