Washington State legalized recreational marijuana during the 2012 Election, but it wasn't until July 2014 that recreational marijuana sales were allowed. At first, prices were unreal. 35-40 dollars per gram was considered to be normal at some stores. Other stores obviously sold it for less, but those were the numbers my friends were paying at some stores. It was a bittersweet, because while it's great that legal marijuana was being sold at stores instead of on the blackmarket, it was hard to make the argument that legal marijuana would eliminate the blackmarket due to the fact that marijuana was so much more expensive at stores.
Fortunately as more growers came on line and started harvesting, prices started to drop. According to Bloomberg News, prices have dropped by as much as 40% at some stores:
Shortages that plagued the start of Washington state's legal marijuana market have eased, sending prices in recreational-pot stores down as much as 40 percent.
Seattle's first pot shop, Cannabis City, ran out of marijuana in three days when it opened in July. Since then, the state has licensed more growers, processors and retailers, increasing supply and reducing prices to an average of $15 a gram, said Randy Simmons, deputy director of the Washington State Liquor Control Board. Prices were as much as $25 a gram in July, including taxes.
In order for legal recreational marijuana to succeed, prices have to be reasonable. They don't have to be at or lower than the blackmarket necessarily (although that would be optimal), but they have to be close enough that people aren't turned off. A big reason for high prices in Washington is taxes, which blackmarket dealers obviously don't have to pay.