With a little knowledge and a few tricks, the flower of kings can thrive in south Louisiana homes.

That's the word on orchids from Dr. Terry Rehn, who will share some of his growing tips at a workshop, "Orchids: From the King's Conservatory to the Grocery Store," at the 29th annual Southern Garden Symposium and Workshops Oct. 20-21 in St. Francisville. 

"You can fairly easily grow orchids that will bloom and rebloom, even if you don't have a greenhouse," said the retired cardiologist and Master Gardener, who has hundreds of orchids in his greenhouse but also experiments with growing them in different parts of his home and garden. 

There are more than 35,000 species of orchids, but Rehn believes that Phalaenopsis, the variety most often seen in garden centers, supermarkets and floral shops, does very well here.

"If you pick one with lots of buds and healthy buds, there is no reason that the Phalaenopsis won't last from one to two months or even as long as six months," Rehn says. 

His No. 1 rule — don't overwater.

"No more than once a week or even every two weeks," Rehn says. "It depends on the plant and the media (what the plant is growing in). You should only water when the media is dry."

Rehn recommends that once a plant is through blooming, repot it in a commercial orchid potting mix, making sure the flower pot has drainage. 

"Each species has a different trigger to bloom," Rehn says. For Phalaenopsis, the trigger is cooler weather.

"The American Orchid Society recommends several weeks with the nighttime temperature of 55 degrees," he says. "You can leave the plant outside in the fall to be in tune to that. When you bring it in, it should bloom."

Stagger the growing sequences to have orchids blooming through the winter.

"You can leave the orchids outside in a covered place with space heaters to keep the temperatures from going down too low," he says. "If you get the right conditions, orchids are very forgiving."

Every three to four weeks, Rehn fertilizes his orchids with products like Miracle-Gro or Osmocote.

"Orchids get 90 percent of their energy from sunlight and about 10 percent from fertilizer," he says, "but they need to be in the shade. That's what the plants want. If you have to put them in a sunny spot, be sure it's only morning sun." 

To prolong the blooming plants inside, Rehn says it's important that they have enough humidity. He often puts his orchids on a baking sheet on top of a plastic rack. Excess water goes into the pan to give the plants extra moisture. 

One of Rehn's favorite orchids is a Cymbidium he cultivated from a blue-ribbon winning orchid at the Baton Rouge Orchid Society's annual orchid show.

"That's the best way to get a wonderful Cymbidium," he said. "The ones sold in the grocery stores here are usually propagated from plants that grow in cold areas. Once they bloom, they are usually over."

Orchids grow on every continent except Antarctic. They were first cultivated in England about 300 years ago, when missionaries, soldiers and travelers would bring plants home with them. After a treaty between the U.S. and Taiwan in 2003 to allow the importing of certain species of orchids in growing media rather than with bare roots, orchids began to flood the market and are now available at very low prices.

Rehn bought his first orchid in Hawaii some 30 years ago and nursed it all the way home.

"When I got to Baton Rouge and was getting off the plane, I knocked off the bloom spike," he says with a laugh. 

Southern Garden Symposium

Leading gardening experts from across the South will present demonstrations and lectures at the 29th annual Southern Garden Symposium and Workshops in St. Francisville Oct. 20-21. 

COST: $170, includes Oct. 20 workshops and lunch and Oct. 21 symposium and tea. Cost for one day is $90. Participants can also attend the Speakers Gala at Rosale, home of Lynda and Peter Truitt, on the night of Oct. 20 for an additional $75.

REGISTER/INFO: Send checks made payable to The Southern Garden Symposium, P.O. Box 2075, St. Francisville, LA 70775. For more information, call (225) 635-3738, email luciecassity@bellsouth.net or visit SouthernGardenSymposium.org

Friday, Oct. 20, presentations

  • "He Said, She Said: A Couple's Approach to Floral Design" by floral designers Tom and Nancy McIntyre
  • A tour of the gardens at Rosedown Plantation State Historic Site led by Trish Aleshire, Rosedown's horticulturist and manager
  • "Plant Mania: The Best and Brightest in New Landscape Plants" by Allen Owings, recently retired horticulture professor with the LSU AgCenter's Research Station in Hammond
  • "Orchids: From the King's Conservatory to the Grocery Store," a tutorial on growing orchids by Dr. Terry Rehn
  • "Secrets from the Asian/Cajun Gardener" at the family arboretum of Walter Imahara and his niece, Wanda Chase
  • "Going on Safari in Your Own Backyard" by Margaret Gratz, columnist for the Northeast Mississippi Daily Journal, garden editor of Mississippi magazine and writer for Mississippi Gardeners magazine.
  • Lunch in Genevieve Munson Trimble's romantic Ruins Garden at Afton Villa Gardens

Saturday, Oct. 21, presentations

  • Update on Louisiana's medical marijuana initiative by William Richardson, LSU vice president for agriculture and dean of the LSU College of Agriculture
  • "Trial to Design: Case Studies from the Dallas Arboretum," by Jenny Wegley, director of horticulture at the Dallas Arboretum and Botanical Garden
  • "Beauty and Utility: Thomas Jefferson's Botanical Laboratory at Monticello" by Peggy Cornett, garden historian and curator of plants at Monticello
  • "Aliens in the Garden: The Good and Bad of Invasive Species " by Brendon Larson, associate professor in the School of Environment, Resources and Sustainability at the University of Waterloo in Ontario, Canada
  • Lunch
  • Tea at Dogwood, the private residence of Rob and Missy Couhig, south of St. Francisville.