MARTIN COUNTY — What a top sheriff’s official called the largest marijuana-growing operation in at least 20 years in the county burned Thursday at a “pole barn” structure off Southwest Fox Brown Road.

Investigators also found about 150 pounds of marijuana ready for distribution in a home, Sheriff’s Chief Deputy John Budensiek said.

“Between six and eight people we think were living there, and it looks like they left in a hurry,” Budensiek said. “I think they knew when that fire kicked off that they had to get out.”

He said a passerby about 3:45 a.m. called in a fire on a 20-acre piece of property. 

The land is in the 9900 block of Southwest Fox Brown Road, which is between Southwest Martin Highway and State Road 710 in western Martin County. 

“Quickly into the investigation into fighting the fire based on the smell they realized that they were fighting a fire involving a significant marijuana grow,” Budensiek said.

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He said the “pole barn” structure, which is about 5,000 square feet, was fully engulfed and nothing was salvageable. Investigators believe it contained about 600 mature marijuana plants.

“What was striking to us was just the amount of electricity that this place was generating,” he said.

About three dozen air conditioning units were there. Air conditioning units are used to keep the interior of the growing area cool because of heat generated by very hot growing lights. He said they got power illegally and were thought to be using stolen transformers.

“The whole thing was clandestine, even the AC units — all 35 of them — were either hidden in the trees which kind of looked like a jungle … or they were covered in like a dark cloth, kind of like something you use in a nursery where water and a little bit of sunlight would come through but if you flew over in a helicopter or anything you will not see what was there,” Budensiek said.

In a Conex container were 50 to 100 baby marijuana plants that didn’t burn.

He said officials found a house where they believe those responsible lived, but they weren’t there. 

“In that house was a significant marijuana grow along with north of 150 pounds of finished marijuana that was packaged for distribution,” Budensiek said.

He said those responsible are thought to have buried discarded items including bottles and chemicals in a hole, and the operation could have been going for years.

He said representatives from Florida Power & Light Co. had to shut the power off.

The property owner is a woman in Miami, he said.

Budensiek said much time was spent collecting evidence, and he’s optimistic arrests will be made. 

“I’ve been pretty much to every significant (marijuana) grow in Martin County in the last 20 years,” he said. “This is the largest that I've seen.”

Will Greenlee is a breaking news reporter for TCPalm. Follow Will on Twitter @OffTheBeatTweet or reach him by phone at 772-692-8936. E-mail him at will.greenlee@tcpalm.com

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