Gary Catalano stood beside his booth Saturday pitching the benefits of his aeroponic marijuana growing system at the Home Grown Maine 2012 medical marijuana trade show.

“It is the cleanest system because it doesn’t use dirt,” said Catalano of Harrison.

Catalano, who runs Catalano Caregivers and Northern Aeroponics, said being able to legally grow marijuana is a dream come true. He said for years he grew marijuana illegally, even though his parents urged him to stop.

“Now I am actually teaching my father how to grow it,” said Catalano, a registered caregiver who under state law may grow medical marijuana for up to five patients.

Catalano was one of dozens of vendors at the trade show, sponsored by the Medical Marijuana Caregivers of Maine statewide trade association.

Held at the Holiday Inn by theBay, one of the state’s busiest convention venues, the show continues until 9 p.m.