Gangs linked to boom in indoor pot farms

California is in the midst of a major boom in large-scale marijuana cultivation operations run from inside homes, with authorities confiscating more than $100 million worth of pot in the last year alone, including in a series of recent raids in the suburbs of Los Angeles.

Officials with the U.S. Drug Enforcement Administration say the number of indoor marijuana plants seized by federal, state and local authorities in California has quadrupled in just the last three years, from at least 54,000 plants to nearly 200,000 in 2006.

Many of those seizures have occurred in middle-class and upscale suburbs, where the pot growers took advantage of cheap home financing -- and minimal credit checks -- to purchase homes and remodel them into sophisticated farms, authorities said.

Using equipment that can cost as much as $75,000, the homes were transformed into illicit greenhouses complete with blacked-out windows, sophisticated irrigation, high-powered and timed lighting and ventilation devices to hide the smell of the plants.

“They have cropped up in neighborhoods like never before,” said Gordon Taylor, who heads the DEA office in Sacramento. “I am not talking about the Cheech and Chong marijuana cultivation of two plants in someone’s closet. I am talking about organized crime groups who are purchasing homes in our communities and creating marijuana factories.”

Local authorities have discovered at least six indoor suburban pot farms in just the last month -- including two this week in Rowland Heights.

The homes have been clustered throughout upscale suburbs with large Asian populations, including Diamond Bar and Chino Hills.

The Los Angeles and San Bernardino County sheriff’s departments have arrested half a dozen people and expect more arrests as the investigations continue.

Since last August, officials in Northern California have arrested 16 people and seized 50 suburban pot homes and 24,000 pounds of marijuana linked to an Asian organized crime syndicate operating in Canada and the U.S.

DEA officials estimate there are 21,000 residential marijuana operations, primarily on the west coasts of Canada and the U.S., and authorities have reported cases in Florida, Georgia and parts of the East Coast.

The boom has occurred as law enforcement has cracked down on marijuana cultivation in forests and canyon parklands.

A recent series of busts in the hillsides and canyons of Orange County culminated last fall with the discovery of up to 20,000 plants flourishing in a hilly park alongside million-dollar homes in a gated Mission Viejo neighborhood. Authorities said they discovered the crop -- which was the largest in the county’s history, with a potential retail value of $12.5 million -- by following an irrigation system that sprang from the local homeowners association’s water supply.

Authorities said the field was hidden beneath brush and other vegetation in an attempt to thwart the county’s regular patrols by foot and air.

“More and more, law enforcement is out there in the wilderness, and that pushes these growers to stay one step ahead of us,” said Orange County Sheriff’s Department spokesman Jim Amormino. “It’s really a pain to search for these grows by foot, to be honest with you, because they hide them so well.”

The suburban homes make sense for criminals because authorities say they can operate with little scrutiny.

Indoor pot plants are smaller than their outdoor counterparts, which are harvested once a year and produce about a pound of the drug. But the advantage of growing indoors, authorities say, is that a new crop is produced every three months or so, which over a year would equal the outdoor harvest.

Also, the indoor plants are shielded from airborne surveillance or interlopers who inadvertently find the plants or try to steal them. Between 2001 and 2005, the DEA reported that the number of outdoor plants seized nationwide rose from 3 million to nearly 5 million. The number of seizures of indoor marijuana plants jumped from about 236,000 in 2001 to 401,000 last year.

Authorities worry that home farms can attract drug violence to normally peaceful neighborhoods.

“Don’t expect them to invite you inside for cookies, because they are trying to protect their indoor grow,” the DEA’s Taylor said.

Assistant Chief Kent Shaw with the California Bureau of Narcotics Enforcement agreed, adding that state officials already have been receiving more reports of crimes connected to the indoor marijuana operations.

“It’s like a pot of gold sitting in those houses, and people are going to do whatever it takes to get their hands on it,” Shaw said. “There’s already been some takeover robberies of indoor grows, some that gets reported, some that does not.”

Also complicating matters for police is the fact that the gangs try to conceal their operations by using layers of growers, dealers and homeowners.

“When you do catch people, you catch the lower-end people, the gardeners and caretakers,” Amormino said. “The kingpins are rarely caught. They may be in another country, you never really know.”

In Southern California, officials are perplexed by the sudden surge in marijuana seizures. In March, officials found an estimated $20 million in pot inside an abandoned truck in San Bernardino County.

On Wednesday, narcotics detectives served a search warrant at the homes in Rowland Heights, said Sheriff’s Lt. Jim Whitten. Homes with similar growing systems have been uncovered in Diamond Bar, Pomona and Chino Hills. Investigators do not know if they are related. More than $40 million in pot has been recovered.

“The two homes in Rowland Heights are connected with the same person on the utilities,” Whitten said.

Officials don’t encourage anyone to take the law into their own hands, but they say neighbors can keep their eyes open for suspicious signs: Homes where trash cans are never taken to the street, where overgrown plants are never trimmed or where the gardener or pool caretaker never comes.

Smith said some pot dealers in Northern California have caught on and now hire gardeners to bring out the trash and trim the grass. Some growers now make several visits to the homes to make it appear that they are home while checking on their crops.

Gang members operating out of San Francisco set up operations in the Stockton, Modesto and Sacramento suburbs.

andrew.blankstein@latimes.com

garrett.therolf@latimes.com

Times staff writer Richard Winton contributed to this report.