In this photo taken on Saturday, Feb. 9, 2013, THC University co-founder Matt Jones, center, speaks to the first class as co-founder Freeman LaFleur, left, looks on at THC University that was held at the Tivoli in Denver. Watery failure is what inspired the “Marijuana 101” class, which was organized by Matt Jones, a 24-year-old Web developer who wanted to get in the marijuana business without raising or selling it himself. (AP Photo/Ed Andrieski)

In this photo taken on Saturday, Feb. 9, 2013, Instructor Ted Smith holds up a chemical that is recommended in growing marijuana during the first class at THC University in Denver. Smith told the first-time marijuana growers that chemical fertilizers work so quickly that some are called “bud rocket.” (AP Photo/Ed Andrieski)

In this photo taken on Saturday, Feb. 9, 2013, instructor Ted Smith uses a slide to demonstrate different types of damage to marijuana plants during class at THC University in the Tivoli in Denver. Chemical fertilizers can be finely crafted to target a specific deficiency in the plants, whether they’re lacking phosphorus, evident by telltale “purple vein,” or potassium, a likely culprit when leaves show brown spots between the veins. (AP Photo/Ed Andrieski)

In this photo taken on Saturday, Feb. 9, 2013, instructor Ted Smith, left, shows Ginger and Heath Grider how to cut and plant a section of a tomato plant during class at THC University at the Tivoli in Denver. Marijuana can be grown from seed, or from a clipping off a “mother” marijuana plant. Clones, as the clippings are called, grow faster and produce smokeable marijuana much more quickly than seeds. But seeds can be worth the wait, producing hardier marijuana. (AP Photo/Ed Andrieski)

** HOLD FOR STORY BY KRISTEN WYATT ** In this photo taken on Saturday, Feb. 9, 2013, a textbook on Marijuana Horticulture sits on a desk during the first class at the THC University in Denver. (AP Photo/Ed Andrieski)

In this photo taken on Saturday, Feb. 9, 2013, Mark Poullin looks at chemicals for use on plants as they are passed around the classroom at THC University in the Tivoli in Denver. Marijuana classes are popping up in Colorado as people seek help growing their own pot. (AP Photo/Ed Andrieski)

In this photo taken on Saturday, Feb. 9, 2013, Cael Nodd listens during class at THC University in Denver. It was intimidating stuff for class attendees like Cael Nodd, a 34-year-old Denver marijuana user who has never tried to grow pot before. “It seems like there’s going to be a sizable investment,” Nodd said. “I want something that really tastes good and looks good. A quality product. Doesn’t seem like it will be that easy.” (AP Photo/Ed Andrieski)

In this photo taken on Saturday, Feb. 9, 2013, Ian Banister looks at chemicals for growing plants as they are passed around the classroom at THC University in the Tivoli in Denver. (AP Photo/Ed Andrieski)