When I first started growing houseplants, orchids were beyond my reach. Not only were they prohibitively expensive, but my bedroom in my parents’ house could not provide the conditions they needed to thrive. Thirty years on, much has changed. Orchids are sold in supermarkets and adorn the windowsills and coffee tables of regular homes, seemingly flourishing without the need for fancy greenhouse conditions. Careful crossbreeding has developed orchid varieties ideal for indoors and mass production in places like Florida ensures we can all afford an orchid or two.
Before describing the basics of orchid care, it’s worth explaining a bit of terminology. Orchids are members of the family Orchidaceae, the second largest plant family on Earth (the daisies are larger). They occur on every continent but Antarctica, are much more common in the tropics, and divide roughly into two categories: terrestrial and epiphytic. Terrestrials are rooted into the ground and include all of Washington’s native orchids. If you grow an orchid in your garden, and there are many fine hardy orchids, the chances are it’s a terrestrial. Epiphytes grow attached to tree branches and are found predominantly in humid tropical forests. Most houseplant orchids are epiphytes, with two exceptions: slipper orchids (Paphiopedilum) and jewel orchids (Ludisia).
As with any houseplant, the key to success is correct watering – a horticulture tutor once told me the secret to orchid care is to cut a hole in the bottom of your watering can! Most orchids have large, fleshy roots that are prone to rot, so only water when the pot feels light and/or the soil is dry. This is especially true for epiphytes; when you live life dangling from a tree, your roots are NEVER sitting in water. Position plants in bright, indirect light; an east- or west-facing windowsill is ideal. Indoor temperatures are fine for most common orchids, though some from cooler climates, such as Cymbidium, enjoy spending the summer outdoors. Feed using balanced fertilizer – there’s no need to buy a specialist product – but dilute to quarter strength and provide weekly, or every time you water. Orchids need repotting either because their roots outgrow the space – often evidenced by roots hanging out – or because the potting mixture is breaking down. Any plastic pot will do, but you must use a soil mix designed for orchids. Terrestrials and epiphytes have different requirements, so make sure you know which is which.
If you’ve never grown them before, then it can be daunting choosing an orchid. The two supermarket staples, moth orchids (Phalaenopsis) and cymbidium are both excellent for beginners. Once you’ve got the hang of them, there are several exciting species to look out for. Coconut orchid (Maxillariella tenuifolia) has coconut-scented blooms, while most Coelogyne produce sweetly-fragrant flowers. The many hybrids of Vanda have remarkably colored flowers and the plants are often grown without soil, simply placed in a glass vase or hung in a window where their long roots trail down. Jewel orchid (Ludisia discolor) flowers are somewhat pathetic, but its dark, sultry foliage endears it to those of a gothic persuasion. With 30,000 species and over 70,000 man-made hybrids, the orchid family has much to offer!
Dr. Ross Bayton
Heronswood Assistant Director
Photos by Ross Bayton