Caring for slipper orchids

Learn how to care for your Paphiopedilum (slipper orchids) from one of our experts.

Where is your plant from?

As with other plants, it is helpful to understand where a plant grows naturally for success in cultivation. They are found growing in south China through to tropical Asia, a few grow as epiphytes, living in trees, whilst the remainder are either terrestrial or lithophytes (growing on rocks). The vast majority that are on sale nowadays will be hybrids, unless you are buying from specialist nursery and so will have been bred to be better adapted to pot culture.

The slipper orchid has long been popular in cultivation as a pot plant and a cut flower, but this, in turn, has proved to be its undoing as many wild populations are under threat. Image: Paphiopedilum villosum in Thailand (Photograph by Lucinda Lachelin)

Long-lasting flowers

The long-lasting flowers are characterised by a distinctive modified lip, or pouch, which is to attract insects for pollination purposes, not for food. The leaves of some can be mottled, which adds to their attraction. Flowering generally is during the winter, but flowers can appear at other times also. Flowers will appear from the centre of the newest growth only.

Watering

In the wild, they often grow on the forest floor in evergreen or seasonally deciduous forests, which means that they prefer shaded conditions. There will be high rainfall and humidity, but also often periods of drought. The thick fleshy leaves and roots enable plants to survive these drier periods, rather than pseudobulbs (swollen stems that look like bulbs) which many other orchids have. In cultivation, it is usually advisable to reduce watering during the winter months, and then to increase this as you see new growth in the spring. When watering ensure that the water runs through the pot and that the plant is not left sitting in water, remembering all the time, that they would be growing in well-drained leaf litter, on rocks or up on tree branches, where there would be perfect drainage.

Potting

Use a bark based compost of medium to fine orchid bark for potting, perhaps with some added perlite and choose a pot that is just large enough to take the roots. Paphiopedilums grown on a large scale, say in the Netherlands, may come in a peat mix with added bark. Spring is the best time for repotting when the plants are putting on more growth. Specialist orchid composts are available from good garden centres and orchid suppliers.

Where to place

Except in the darkest days of winter, slipper orchids should not be kept on a south-facing windowsill, an east or west position is best and perhaps slightly set back from the window in summer. Minimum temperatures of about 10–13°C is suitable for most, rising to around 25°C. A variation in temperature during the day is beneficial, as it is for many plants, to promote flowering.

Lucinda Lachelin
Botanical horticulturist
Oxford Botanic Garden and Arboretum

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