How Grow Houses Work

Controlled Substance Image Gallery An oscillating fan cools down the crops in a grow house. See more ­controlled substance pictures.
Controlled Substance Image Gallery An oscillating fan cools down the crops in a grow house. See more ­controlled substance pictures.
Owen Franken/Stone/Getty Images

­Nothing s­pruces up a house quite like a few potted plants. They freshen the air, brighten your mood and really bring a room together. Plus, if just one of those house plants happens to be a Cannabis sativa, you could wind up with maybe a half-pound (227 grams) of marijuana worth close to $1,000, depending on the going market rate. Avoid going to jail and that's enough to add some serious pizzazz to any living room. But if one plant can generate that kind of cash, why not just fill the whole house with marijuana plants?

Sound like a great idea? Well, pot producers are way ahead of you. Indoor marijuana crops are big business for two key reasons. First, if you're going to grow an illegal cash crop, it's best to do it where police helicopters and passing motorists won't notice. Second, growing marijuana indoors allows you to cultivate stronger pot and more of it. So even in areas where growing marijuana is decriminalized or legal, it often makes more sense to take the operation inside -- often into residential homes.


If ­you devote a room in your house to cultivating marijuana, you have a grow room. Set aside most of your available indoor space to this inve­stment and -- voila -- you have a grow house­. It may sound extreme, but the practice is far from isolated. In fact, in some areas, the statistics are downright staggering. In Humboldt County, Calif., where cultivating medical marijuana enjoys limited legal protection, law enforcement officials estimate up to 1,000 of the 7,500 homes in the community are grow operations [source: Los Angeles Times]. In Vancouver, Canada, the estimate runs as high as one out of every five houses [source: Cannabis Culture].

This may seem like a lot of effort just to grow a few plants, but billions of dollars are wrapped up in the sale of marijuana. Of course, not everyone who grows cannabis is in it strictly for the money. Some growers believe in the health benefits of the herb, while others simply like getting high. But many individuals and criminal organizations set up grow houses because the money is simply too good. As with any contraband item, the unregulated and illegal nature of the product pushes prices through the roof. And to cap things off, the market is huge. In the United States alone, at least 14.8 million people use marijuana -- and an estimated 6,000 people a day try it for the first time [source: NIDA].

­In this article, we'll look at what goes into setting up a grow house, who runs them and how law enforcement tries to harsh everyone's mellow.

Setting Up a Grow House

Operating a grow house is a little more involved than remembering to water the plants everyday.
Operating a grow house is a little more involved than remembering to water the plants everyday.
© Long

­For the avid marijuana grow­er, dealing with lawmakers, police officers and distributors can be quite a hassle. But on top of the various human demands, they have a plant to appease. Cannabis sativa isn't interested in medical findings, legal jurisdiction, bribes or profits. It needs sunlight, water, warmth and nutrients. If growers give the plants what they need, then they can harvest all the green gold they want.

Of course, most homes are designed to house human families -- as opposed to, say, a few hundred cannabis plants. To meet the needs of a large, indoor marijuana growing operation, some do-it-yourself additions are required. In larger, professional operations, the costs of outfitting a home can cost hundreds of thousands of dollars, transforming the home into a closed growing environment. Some of these grow houses are home only to plants and the machines that keep them alive.


­What kind of digs do these plants require? First, marijuana plants have to sink their roots into something. Most growers use a calculated mixture of nutrients, fertilizer and soil. Another method is to employ hydroponics, in which the grower uses nutrient solutions instead of soil and supports the plants in specially designed containers, trays and tables. Second, plants need water, which demands either manual or automated watering, such as a drip system. To prevent overwatering and water damage to the house, growers have to make sure proper drainage is in place. Growers often try to lock all this moisture inside with airtight seals and insulation, but sometimes dehumidifiers are required if the air becomes too damp.

Water and nutrient-rich soil won't help a plant one bit, however, if it doesn't get enough sunlight. Given the limits of indoor growing, artificial lighting is required. Luckily for grow houses, horticulture and aquarium lights are readily available. After all, not everyone who grows plants indoors is in the marijuana business. Successful grow house operators recommend using 1,000-watt horticulture bulbs, each of which can sustain 15 to 20 plants [source: Cannabis Culture]. To put that in perspective, incandescent light bulbs typically range between 40 and 150 watts, while compact fluorescent light bulbs use between 9 and 52 watts.

By controlling how much light the plants get, growers can also speed up the growth cycle for the female plants that produce the valuable buds. It's as if your boss secretly set all the clocks in the office back a few hours to squeeze a little extra work out of everyone. During the initial growth period, grow house crops enjoy 16- to 18-hour days to hurry development. Toward the end of the growth cycle, growers shorten the days to cause the plants to flower. By employing this method and growing only the bud-producing female plants, grow house operators can produce as much as four times as much pot as an outdoor operation [source: New Yorker]. The plants are typically scrawnier, but contain more of the THC-laden resin that makes marijuana use so popular.

­How hot can a room full of 1,000-watt ­light bulbs get? In the next section, we'll look at the problems these lights pose and how growers protect their investment from pests and diseases.

Cooling the Marijuana Crop

­­All these lights can pose numerous problems. For starters, the electrical wiring in most living rooms is only capable of powering a single 1,000-watt bulb. To power more lights and additional electrical devices, you're going to have to perform quite a bit of rewiring or hire an electrician who doesn't mind getting his or her hands dirty. Plus, to cut down on the massive amounts of electricity numerous lights require, growers often stagger their "days" among different rooms in the grow house so that a minimum amount of power is required at any given time.

­There's another side effect to stuffing a house full of horticulture lamps: incredible heat. Without proper ventilation and air conditioning, many grow houses would experience nighttime temperatures of more than 100 degrees F (38 degrees C). This isn't just a matter of cutting down on how many grow house workers succumb to heat stroke. Marijuana grows best at temperatures between 70 and 80 degrees F (21 and 27 degrees C), but can thrive at 95 degrees Fahrenheit (35 degrees C) in a well-lit, CO2-heavy environment. Growers also keep planters and pots elevated on tables to keep root systems away from the cooling influence of floors.


Growers use air conditioning and ventilation fans to maintain a constant temperature for their marijuana crop. Every 1,000-watt bulb requires one fan and 2,800 British thermal units (BTUs) of cooling [source: Cannabis Culture]. To put that in perspective, a typical 5-ton air conditioner puts out around 60,000 BTUs. As stated above, sustaining very high levels of CO2 permits higher temperatures. This is because the hotter it is, the more CO2 marijuana plants consume, which also results in thicker buds. But the constant use of powerful air conditioners also increases a grow house's demand for electricity, as well as water in the case of water-cooled units.

­Finally, marijuana plants are subject to harm from a host of parasitic insects, spores, fungi and mildews. Some growers use ionizers and ozonators to control pests and remove harmful agents for the air. Others champion the use of charcoal filtration systems or just regularly increasing CO2 levels high enough to kill harmful pests. Plus, growers who seal off everything in a closed growing environment decrease the risk of outside contamination.

­Appeasing the plants is one thing, but operating under the radar of law enforcement is another. On the next page, we'll look at what measures growers take, as well as how cops try to snatch their crops.

Keeping Grow House Operations Under Wraps

Young cannabis clones grow at the Los Angeles Cannabis Resource Center.
Young cannabis clones grow at the Los Angeles Cannabis Resource Center.
Dan Callister/Getty Images News/­Getty Images

Cultivating indoor cannabis requires a lot of time, labor and money. You'd encounter many of the same kinds of costs if you decided to stuff a suburban home with zucchini plants. The difference, of course, is that law enforcement agencies aren't going to waste tens of millions of dollars in an effort to snuff out clandestine zucchini growing operations. Marijuana growers spend a great deal of money just keeping their operations hidden from prying eyes.

While some grow houses operate in secluded rural areas, many thrive in the close confines of suburban communities. In either case, growers need their facilities to look, sound and smell like just another dwelling. They have to make sure outward appearances don't tip anyone off, which means making sure the house looks more like someone's home and less like a dope factory. This ca­n entail everything from waiting until the least suspicious times to transport goods to buying yard gnomes. ­


Even if everything looks sound, growers still have to worry about the neighbors' noses. Marijuana has a strong, distinctive odor -- and hundreds of plants smell even stronger. To combat this threat, growers either use charcoal filters for outgoing air or maintain a closed growing environment. With the latter method, growers seal plant areas off from the outside world with plastic and nurture the plants with CO2­ from tanks or natural gas burners.

Effectively sealed off from the five senses, you might think the crops would be safe at this point. But law enforcement has two key allies in the war on drugs: water and power companies. A house with 1,000-watt electrical lights, constant air conditioning and an array of pumps, filters and monitoring equipment will generate quite a power bill. When electric companies notice unreasonably high power usages or patterns of use that fall in line with grow house light cycles, they go straight to the authorities. These conditions leave two options for grow house operators: either make your own electricity or steal it.

Gas-powered generators allow growers to either supplement legitimate power usage or provide all the electricity for lighting. It takes about 80 kilowatts to keep a 50-light grow room burning [source: Cannabis Culture]. Generators capable of meeting these demands typically run between $10,000 and $20,000, along with fuel costs. Generators bring the added risk of mechanical malfunction and fire, as well as the demand for frequent and possibly suspicious fuel purchases. Plus, if you've ever heard a generator, you know even the small models make a lot of noise. While the constant roar of a gas motor might fly in a secluded, rural setting, suburban neighbors would probably grow irritated and suspicious in no time. But with enough soundproofing and proper ventilation, some growers are able to maintain generators in insulated basement areas.

In order to steal power, marijuana growers either tamper with power meters or reroute incoming electricity around them. Both of these methods bring with them the risk of fatal electrocution and detection by power line inspectors. Some grow house operators cut down on the risk by employing former or even current power company workers to commit these crimes. They steal water in similar ways, such as drilling holes through the paddles that measure water flow into a home.

If the bill for indoor pot farming seems astronomical, then just hold on. We haven't even looked at what goes into manning a grow house.

Managing a Grow House

A U.S. federal law enforcement agent removes grow lights during a raid on a medical marijuana club in California. While such operations are legal under California state law, they are still criminal operations in the eyes of the U.S. Drug Enforcement Agency.
A U.S. federal law enforcement agent removes grow lights during a raid on a medical marijuana club in California. While such operations are legal under California state law, they are still criminal operations in the eyes of the U.S. Drug Enforcement Agency.
Justin Sullivan/Getty Images News/­Getty Images

­As with any business, marijuana grow operations vary greatly in size. On one end of the spectrum, you have mom-and-pop operations: pot enthusiasts and medical marijuana growers that manage, at most, a grow room or two. A dedicated small-timer might even set aside a large portion of his or her home to cultivating cannabis. Full-blown grow houses, however, often aren't even inhabited by the people who own them. And the operators themselves may manage as many as a dozen grow houses in a given area.

You have two factors at the heart of most grow house operations: money and management. Sometimes, they're wrapped up in the same person or group of people. Other times, the funding for a grow house comes down from secretive investors and organized crime. Either way, someone has to oversee the purchase of materials, renovations, setup and staffing in person.­


Plus, if you're going to fill a space with millions in illegal cannabis crops, you're going to want to avoid pesky landlords by purchasing the property. In some cases, grow house operators buy the houses they use, using crooked real estate agents and taking advantage of loose lending standards. Other times, the larger criminal organization pays for the property and merely places the operator in charge of running it. As with any illegal undertaking, the people with the most money tend to distance themselves as much as possible from the actual illegal activity.

­Once a grow house is up and running, someone has to see to daily care and maintenance, as well as provide security against other criminals who want a slice of the cannabis pie. In the Pacific Midwest, Vietnamese immigrants fill many of these positions [source: NPR]. Some operations in the U.S. and Canada use a form of indentured illegal immigrant labor. When criminal organizations smuggle individuals into a country, they often demand payment in the form of labor. Some are shuffled into prostitution, others wind up tending indoor marijuana crops. When it's time to harvest, the operator may bring in additional, temporary workers.

­So why does anyone have a problem with secretive neighbors who mostly keep to themselves? In the next section, we'll look at why some homeowners consider grow houses bad neighbors.

Bad Seed: Living Next Door to a Grow House

Under the protection of California state law, medical marijuana shops offer products such as cannabis chocolate bars, cannabis baked goods and even cannabis beer.
Under the protection of California state law, medical marijuana shops offer products such as cannabis chocolate bars, cannabis baked goods and even cannabis beer.
Bob Berg/Getty Images News/Getty Images

Imagine neighbors who don't ask to borrow your tools, never throw loud house parties and keep a low profile. So what if they aren't that friendly, at least they don't keep you up at night. Why should their massive, midnight deliveries of plant food and blacked-out windows make you nervous?

­The police aren't the only critics -- real estate agents, residents and even small-time medical marijuana growers have voiced concerns over grow houses in suburban areas. Safety is the key concern. Whether you see marijuana as a harmless herb or a serious threat to civilization, its status as an illegal drug means a potentially dangerous criminal element may be involved in a grow house operation. Your neighbors might actually be illegal immigrants forced to work off a smuggling debt or armed criminals intent on protecting their crops.


Grow houses also pose considerable fire risks due to custom electrical rewiring and the use of hot grow lamps. And when growers pirate electricity from the local power grid, they often put the entire neighborhood at risk for electrocution and fire. And if you're at all concerned about the environmental impact of coal-burning power plants, you might want to adopt a harder stance against indoor marijuana operations. Grow houses often consume six times more electricity than a typical family, maxing out transformers in the process [source: Arcata Eye]. All of that energy puts an additional strain on power plants, producing even more pollution.

In the Pacific Northwest, former grow houses have often resold for more than the growers paid for them, but this isn't always the case [source: Kaste]. When grow house operators leave a property or wind up behind bars, many homes are left a gutted shambles due to rewiring, water damage and a general disregard for any future human habitation. Real estate professionals charge that these operations can lower the price of the house and surrounding homes. Plus, families often have a hard enough time finding a suitable house under normal market conditions. But when your house-hunting competition also includes criminal organizations looking for a dozen homes to grow pot in, selection grows more limited and prices go up.

Want to learn more about marijuana? Explore the links on the next page and allow us to shotgun you even more information.

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