Home & Garden

Now that pot’s legal in California, here’s how to grow it indoors and outdoors

How to set up an indoor garden for cannabis

Chris Corsello of J Street HydroGarden in Sacramento shows what's needed to grow sun-loving plants such as cannabis indoors. Proposition 64 takes effect in California on Jan. 1, 2017, allowing recreational use and limited growing of cannabis.
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Chris Corsello of J Street HydroGarden in Sacramento shows what's needed to grow sun-loving plants such as cannabis indoors. Proposition 64 takes effect in California on Jan. 1, 2017, allowing recreational use and limited growing of cannabis.

At his midtown hydroponics gardening store, Chris Corsello saw many of his customers face a similar dilemma: They wanted to ask his advice but not tell him what they were growing.

“They’d hem and haw,” Corsello said. “You’d sort of look at them sideways and ask, ‘What kind of plant are we talking about?’ 

Neither side would say, he said. Confirming the plant was marijuana could have put Corsello and his customer in jeopardy.

Proposition 64 changed that, and a lot more, by making California cannabis gardening and recreational use legal as of Jan. 1.

“Indoor growers can now come out of the closet,” said Corsello, who owns J Street HydroGarden in Sacramento.

After Proposition 64’s approval, many California gardeners – as well as non-gardeners – are expected to try their green thumbs at cannabis cultivation.

Legalization also is expected to be a boon to the emerging hydroponics industry. Without soil, hydroponic systems grow plants indoors in mediums such as lava rock or perlite and nutrient-rich water.

“It’s already starting,” said Corsello, who opened his gardening store in 2009. “We’re getting a lot more phone calls. Then next year, it will really kick in.”

Outdoors, marijuana grows like a weed. That’s an appropriate nickname, especially in California, where the climate is ideal for pot cultivation. Planted after frost, it’s a seasonal crop with one fall harvest.

But outdoor pot gardens don’t necessarily make good neighbors, Corsello said. “There can be legal issues, and not everybody likes their smell.”

Indoors, cannabis needs artificial light to replicate the sunlight it would get outdoors. Although many sun-loving plants refuse to flower indoors, cannabis can adapt to life inside.

After decades of restrictions and possible legal repercussions, indoor cultivation has become the norm, say experts.

“It’s not that difficult,” said Ed Rosenthal, America’s best-known cultivation expert. “Actually, millions of people are doing it right now in the U.S., hundreds of thousands in California.”

Rosenthal, author of more than a dozen cannabis gardening books, wrote the official course book for famed cannabis school Oaksterdam University, “Ed Rosenthal’s Marijuana Grower’s Handbook” (Quick American Publishing, 510 pages, $29.95). In a recent phone interview, he offered advice for novice growers. After all, he has decades of experience.

“I was in the first wave of smokers in the ’60s,” Rosenthal said. “Nobody thought it would take 50 years (for partial legalization) – unbelievable.”

First, know the law

Under Proposition 64, adults age 21 and older in California may possess up to 1 ounce of dried and processed marijuana and grow up to six plants in their homes. Further refinements such as local taxes, permits and restrictions will come in the months ahead. Find out about local regulations before setting up equipment or digging up the backyard.

Cannabis possession or cultivation is still illegal under federal law and in 21 states, Corsello noted. That has hampered online sales of growing equipment, fertilizers and other items directly targeted to cannabis gardeners.

Until recently, members of the hydroponic and nursery industries were reticent to discuss growing marijuana with customers, Corsello said. People worried that such advice or marketing could cause legal problems, too.

“Now, people are much more open about talking about it and offering advice,” Corsello said.

Consider the plant

A relative of hops, cannabis is a very unusual plant. It acts similar to a poinsettia; periods of total darkness trigger bloom.

“It’s the only annual I know with separate male and female plants,” Rosenthal said. “It can mature and flower at any height, a foot tall or 5 feet; it’s up to you. As a gardener, I find it fascinating to grow.”

With long sticky “hairs,” female flowers – the buds – are consumed, either smoked or via food. (The yellow male flowers look similar to mustard.)

To thrive, any plant needs light, water and fertilizer. Finding the right balance is key to success.

“No plant is hard to grow as long as you meet its requirements,” Rosenthal said.

“Marijuana has three definitive periods of its life: vegetative (when it’s growing only leaves, stems and roots), flowering and then it dies,” he explained. “It needs different things during each phase.”

Marijuana responds rapidly to fertilizer. During the vegetative period, fertilizers high in nitrogen encourage lush growth. (For in-soil growing, bat guano is a longtime favorite.) During flowering, liquid fertilizers high in potassium and phosphate encourage large buds.

“Most plants have a maximum that no matter how much you feed it, they won’t get any bigger or bear more tomatoes, for example,” Corsello added. “Cannabis is unusual in that, the more you feed it, the more it grows. The more it flowers.”

Where to grow?

In most jurisdictions, local authorities will make that decision for you, with restrictions on plant locations as well as numbers. Under Sacramento’s current ordinance, cultivation is restricted to indoors only.

Outdoors is easier and far less expensive but strictly seasonal. The sun provides free light, an automatic savings on electricity. (Indoor grow lights for a 3-foot-by-3-foot growing area can cost $25 to $50 a month to operate.)

Full sun – preferably 18 hours of exposure a day – is preferred for rapid vegetative growth. When uninterrupted darkness reaches more than 12 hours per night, the plants start to flower.

A greenhouse is an option. It makes use of the sun and natural darkness while protecting the plant – indoors – from frost. Greenhouse growth is usually seasonal, although a few flowers could be squeezed into winter.

“A greenhouse has all the advantages of growing outdoors – free light and seasonal growth,” Rosenthal said. “You could set out plants in a greenhouse right now and they would bloom immediately. The plants wouldn’t be very tall, but they’d have more than 12 hours of darkness and that’s what they need.”

Indoor lighting allows for manipulation of the plant’s biological clock, forcing it to bloom sooner. Instead of one crop per year, three crops can be produced annually. As long as they get enough light, plants may be grown in soil in containers or hydroponically.

“I like dirt and sunlight,” said comedian and magazine editor Ngaio Bealum, a well-known Sacramento cannabis advocate. “Greenhouses are great. Hydro can be tricky, and I wouldn’t recommend it for a first-time grower unless they have a homie that is already pretty good at it.”

Danny Danko, senior cultivation editor for High Times magazine, also leans toward soil for first-time growers.

“I prefer soil for beginners because it’s more forgiving than hydroponics,” Danko said. “Growing in soil is a slower process, but hydroponics can tend to magnify mistakes.”

Rosenthal likes hydroponics. “People think of hydroponics as being extremely difficult, but you can get it right the first time,” he said. “It’s fun to do.”

What to grow

Hundreds of cannabis strains are available. Most fall into two cannabis species – indica or sativa – or hybrids. Some strains are easier to grow than others. Initially, seed and clones – rooted cuttings – will be available at California dispensaries.

“Strains go in and out of popularity,” Rosenthal said. “New varieties come out all the time because these plants are so easy to breed.”

For beginning growers, Rosenthal recommended: “Sour Diesel and the whole Diesel family (of hybrids), Master Kush, White Widow, Black Russian, Head Band and Blue Dream.”

“Blue Dream is easy to grow and a big yielder,” Bealum said. “I also like Odyssey, if you can find it. Kushes can be troublesome for first-timers.”

“Indica-dominant strains are easier to grow indoors because they don’t tend to stretch (grow tall) as much as sativa-dominant ones and have shorter flowering times,” Danko said.

Basic needs

“What the plant requires is lots of light,” Rosenthal said.

Indoors, that means lights specifically designed for growing plants. Rosenthal recommends high-pressure sodium lamps, which can get pricey.

“The bulb itself runs $40 to $80,” Corsello said. “And you need a special lighting ballast (which regulates the current to the bulb). They start at $89 to $120.”

That also means that a growing area needs to be set up relatively close to a three-pronged electrical outlet with easy access to water, too. During growth, each plant needs about 1 gallon per day.

“(If growing conventionally), plants need good soil and ample room for roots,” said Rosenthal, noting marijuana prefers well-drained, compost-rich soil. “It need lots of fertilizer, too.”

After that, it’s up to your budget. The lights get hot, so fans are needed. Air filters control strong scents. Grow tents maximize the light by surrounding the plant with reflective surfaces. (HydroGarden sells a basic starter kit including lamps for $450.)

“I like grow tents for their ease of use and the ability to put them up and take them down quickly,” Danko said. “They’re affordable and yet have built-in things like poles for hanging your grow light and holes for exhaust fans. My usual recommendation for a beginner light is a 400-watt HID (high-intensity discharge) light such as a MH (metal halide) or HPS (high-pressure sodium).”

Get good advice

“Make friends with staff at your local gardening store,” Rosenthal said. “They can give you a lot of good advice.

“The best thing people can do is buy a book,” he added. There are hundreds available including his detailed guides.

Bealum recommends Rosenthal’s “Marijuana Buds for Less,” “a great book about how to grow a decent amount of pot with a really inexpensive setup.”

Beginner’s mistakes

Like any gardening hobby, beginners tend to make mistakes. Often, they kill plants with kindness. Marijuana is no exception.

“Overwatering and overfeeding are the most typical problems for beginners,” Danko said. “Also, not using lights that are strong enough and meant for growing plants indoors.”

It’s easy to get caught up in gadgetry and lose track of the plant’s basic needs.

“Never put ‘minor’ before ‘major’ when it comes to growing,” Dank added. “Plants need light, water, food and air circulation. Dial them all in and stay out of the way if things are working. Patience is a virtue, although if you see any signs of a pest problem, you must act immediately.”

The most common marijuana pests also attack other ornamental plants.

“Spider mites are quite typical,” Danko said. “Whiteflies, aphids, fungus gnats and thrips (are common) as well. Powdery mildew can be a problem, especially in more humid areas.”

Rosenthal recommends his own organic pesticide, Zero Tolerance. It’s available via his website.

A growing machine

If all this gardening sounds complicated, Uri Zeevi has an alternative. It’s the Seedo home cultivator, due out in summer 2017 but already a viral sensation.

A little bigger than a mini-fridge, the auto-grow unit – which will cost more than $1,000 – is designed to grow cannabis or other plants from seed to harvest in 100 days or less. The totally contained hydroponic system uses 260 watts of electricity and 75 percent less water than conventional in-soil growing. (It also works well with strawberries, peppers and cherry tomatoes.)

“The goal of our company is to make the growing process easy and accessible to anybody,” said Zeevi, Seedo’s CEO. “The world is racing fast forward in high tech. Eventually, people will grow at home whatever they want.”

Results from recent elections brought about new rules on the use of recreational and medicinal marijuana in several states, with more than half now allowing for the later. Federal government leaders including President Trump have voiced their opin

Debbie Arrington: 916-321-1075, @debarrington

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