A higher grade of pot

Wally looks over cloned marijuana plants that are available for sale at the Long Beach dispensary. Patients are allowed to purchase only a small number of them to grow at home.  (Genaro Molina / Los Angeles Times)

Wally looks over a marijuana plant. Much is riding on his experise at cultivation; the owners of the Long Beach dispensary say they have invested $400,000 in the build-out so far.  (Genaro Molina / Los Angeles Times)

With the help of a magnifying glass, Wally tries to gauage the THC content of a marijuana bud. Over the years, he grew to recognize the myriad subtle and changing needs of the herb.  (Genaro Molina / Los Angeles Times)

Wally tends to plants in a grow tent at the Long Beach outlet. The industry is shifting cultivation from clandestine rural plots to highly controlled indoor grows in urban centers.  (Genaro Molina / Los Angeles Times)

A wide variety of medicinal marijuana buds are available for patients at the Long Beach dispensary. The many combinations of chemicals in pot plants produce a complex range of sensations.  (Genaro Molina / Los Angeles Times)

Budtender Cruz Juarez, 28, left, prepares to fill an order for a patient at the Long Beach dispensary. “Consumers have quickly developed a sophisticated palate,” said Andrew McBeth, publisher at the marijuana niche Green Candy Press.  (Genaro Molina / Los Angeles Times)