Taking the mystery out of orchid care

Orchids, orchids everywhere.

The privileged class used to be the sole growers of orchids, boasting conservatories — and gardeners — on their estates. But today, with at least 28,000 species and well over 300,000 registered cultivars, the Orchidaceae constitutes the largest family of flowering plants in the world. And you can pick one up at Trader Joe's for as little as $7.99 any day of the week. With the right light and just a little bit of care, orchid blooms will last weeks, and possibly months. They pack a lot of bang for the buck.

Stephanie Johnson-Toliver, senior gardener at Seattle's Volunteer Park Conservatory and master orchidist, shares tips on how care for orchids. She and a team of three other gardeners are charged with the care and display of more than 2,000 orchids from all over the world at the conservatory.

"Orchids are like friends," she said. "There are times when they require your undivided attention, and other times just a quick check to see that all is well."

Easy plants: For beginners, Johnson-Toliver suggests four widely available orchids that thrive in a typical home environment — about 70 degrees in the daytime and 55 degrees at night.

• Phalaenopsis (fayl-eh-NOP-siss) or moth orchid has lavish sprays of colorful flowers and will tolerate a very low-light condition.

• Paphiopedilum (paff-ee-oh-PED-ih-lum) or lady's slipper is a compact plant that prefers cooler temperatures. Its single flower can last for months. It thrives in an east or south-shaded window.

• Oncidium (on-SID-ee-um) has long, delicate sprays of tiny yellow and brown spotted flowers in the spring. It requires good light.

• Cymbidium (sim-BID-ee-um), with its long-lasting waxy flowers on thick spikes, is easy to grow — if you have the room and lots of indirect bright light.

Light: Most orchids like at least four to five hours of good natural daylight, preferably in windows not facing west.

Watering: A good rule of thumb is to let your orchid dry out slightly between waterings so air can circulate between its roots. Orchids like plenty of humidity, but most varieties don't like wet feet. Stick your finger in the pot — if it feels a bit dry, it's time to water thoroughly.

Feeding: A full dose of fertilizer once a month is too much at one time. Instead, dilute a full feeding to quarter strength, and give your plant a little bit when watering. Remember to use plain water once a month to flush the orchid, and prevent any salt build-up in the pot.

A fertilizer that has a high first number, such as 30-10-10, which indicates high nitrogen, can be used all year.

When you want to encourage blooms, switch to a high bloom fertilizer like 15-30-15, which has twice the phosphorus as nitrogen. Once you see the flower spikes appear, go back to your regular fertilizer. When the bloom spike is finished, clip it back to the node just above the base of the plant.

Repotting: Orchids benefit from an annual repotting, preferably in the spring, but never in the summer. Orchids prefer cramped conditions, so just slightly increase the pot size. If the change is too dramatic, the plant may rot.

Carefully remove the orchid from the bark. You may need to run water over the roots to loosen them and to remove bits of bark.

Use a sterile, sharp clipper to judiciously clip away dried or stringy roots, leaving the plump roots untouched. Also remove unhealthy-looking leaves.

Use a damp mix that is two-thirds medium bark with a bit of peat and a bit of pumice mixed in. Place a little bit of the mix into the pot. Gently set the plant inside the pot. Cover the roots and fill in the sides with more planting mix.

Tamp the bark around the edges with a stick to secure the roots in the medium. Refrain from watering for several days, so the plant will be forced to send its roots down into its new home.

Robyn Roehm Cannon is a Seattle freelance writer

Information in this article, originally published March 10, 2007, was corrected March 12, 2007. A previous version of this story incorrectly stated the phone number for a workshop on orchid care at the Volunteer Park Conservatory. The correct number for the March 17 workshop is 206-322-4112.