Selma Mansion is known for paranormal activity, including apparitions, disembodied voices, moving objects, and the scent of roses associated with past residents like General Porter and a Knox family wife. The phenomenon is so pronounced that the Norristown Preservation Society, which maintains the property, has hosted ghost hunts and other paranormal events to raise funds. General Porter is reportedly seen pacing in his former study, and full-bodied apparitions have been witnessed by staff and visitors. Whispers, footsteps, and even piano notes have been heard in areas where there is no piano. A poltergeist is said to cause physical effects in the kitchen, such as objects moving or being thrown. The signature scent of roses is sometimes detected, linked to a wife of a general who lived at the mansion.