How to Prune Orchids

Many home gardeners are extremely passionate about orchids. Exotic, delicate orchids delight plant-lovers with their fragile, intricate blooms, which in some varieties occur only once a year.

There are more than 28,000 recognized species of orchids. The most common in the U.S. belong to the Phalaenopsis genus, also referred to as moth orchids, as well as the Cattleya genus. These are considered some of the easiest to grow and coax into gorgeous blooms.

Successfully keeping and cultivating orchids requires care, patience and dedication, as well as a light hand with pruning. Read on to learn how to prune orchids.

Why Prune Orchids

While orchids don’t require cutting back like many plants do, routine pruning — think of it more like grooming — can keep the plant healthy.

“Dead, dry or brown leaves and flower spikes and diseased portions can be removed,” says Nick Ewy, director of collections for the Naples Botanical Garden in Naples, Florida. He also says that when re-potting orchids (more on that below), you can remove any dead roots.

Know Your Orchids

Before pruning your orchid(s), you need to know which species of orchid you have. “Make sure to know your plant,” Ewy says. “Many plants, such as dendrobiums, will bloom on old, leafless pseudobulbs (the bulbous structures that grow below the leaves), so you wouldn’t want to cut those away.”

Also, adds Ewy, “some plants may bloom on the same flower spike for a prolonged period, such as Psychopsis species, so you would not ever want to cut off the flower spike after flowering.”

Knowing your plant type will also help you determine whether the orchid’s appearance is normal or a sign of an unhealthy plant. “Many species, such as cigar orchid (Cyrtopodium puntatum), Dendrobium species (nobile, anosmum, aphyllum ) and most species in the subtribe are deciduous and will lose leaves during the winter or dry season,” Ewy says.

Old specimens of several types may naturally lose old leaves or growths, but that doesn’t mean they’re dead or dying. But other changes in the plant’s appearance could spell problems, Ewy says, “including a bacterial or fungal infection, virus, sunburn, root loss, desiccation, or cold or heat damage.”

If you no longer know the species of orchid you have, the American Orchid Society web site can help you identify your plants and potentially diagnose any problems.

When to Prune Orchids

There’s no specific time of year to prune orchids; their care depends more on each plant’s blooming schedule. In most cases, do some clean-up once the plant is finished blooming. “Basic grooming can happen anytime,” says Ewy, “but problems and corrective measures should be addressed as soon as possible.”

He also says dividing or moving orchids to bigger pots should happen “when the plant is actively vegetatively growing.”

How to Prune Orchids

Wilted orchid blooms can be pinched off with your fingers. For everything else, a little surgery is required.

• Use a sterile tool. Orchids are susceptible to viruses, which they can acquire from contaminated garden tools. “A sterile cutting device should be used any time any living portion of an orchid is cut to prevent the transmission of disease,” says Ewy. He suggests using a torch or flame to heat up old clipping sheers in between cuts. Or use cheap, disposable straight edge razors.
• Don’t overdo it. Remember, you’re only cutting back dead or dry leaves and flower spikes, and only if you’re certain that the spike won’t produce more flowers later in the season.
• Handle with care. Re-pot your orchids every two years, but don’t select pots that are too big for the plant. “Transplanted orchids may decline if installed into pots that are too large,” says Ewy, “so choose a pot that only allows for a year or two worth of growth.”
• Assisted reproduction. Some orchids produce rhizomes, while others produce keikis, or babies. Whichever you have, to divide your single orchid into multiple plants, gently cut the keikis or rhizomes apart with a sharp, sanitized blade. Don’t cut different plants with the same blade without sanitizing it in between.
• Clean and sturdy. Ewy suggests using flower stakes to position growths and flower spikes in the desired position. Also keep the plants clean. “Wipe down leaves if dust, dirt, water spots accumulate,” he says.

Fun Orchid Facts

Here are a couple things you may not know about orchids:

• Orchids grow on every continent except Antarctica. That means you can keep orchids in most parts of the U.S., though Ewy says “plants will generally grow better outside if the climate meets their needs for temperature and humidity.” Orchids love the balmy environment of the Naples Botanical Garden, but might not like Minnesota winters. If you keep your plants indoors, be sure they are kept in humid conditions and get plenty of indirect sunlight.
• One of the rarest orchids in the world grows in Southwest Florida. If you want to wade into waist-deep swamp water in the Everglades between June and August, you might catch sight of an elusive ghost orchid. Just don’t touch it — it’s an endangered, protected species.