From Philadelphia, where they were grown only in greenhouses, John Grimke Drayton (Magnolia's owner) imported the plants for use in his estate garden.With encouragement from Charles Sprague Sargent from Harvard's Arnold Arboretum, Magnolia Gardens was opened to the public in 1871, following the American Civil War.[8] Azaleas and rhododendrons were once so infamous for their toxicity that to receive a bouquet of their flowers in a black vase was a well-known death threat.[11] Azalea is dangerous to pets, as, if consumed, the toxins within the plant tissue can cause central nervous system depression, which in turn can lead to multi-organ failure.Symptoms may include vomiting, diarrhea, seizures, laryngeal edema and heart rhythm disturbances, which can lead to complete cardiac arrest and therefore death.[citation needed] Sobaeksan, one of the 12 well-known Sobaek Mountains, lying on the border between Chungbuk Province and Gyeongbuk has a royal azalea (Rhododendron schlippenbachii) festival held on May every year.Mobile, Alabama is also home to the Azalea Trail Maids, fifty women chosen to serve as ambassadors of the city while wearing antebellum dresses, who originally participated in a three-day festival, but now operate throughout the year.