Only a handful of Uruguayans had registered by midday on Wednesday to be private growers of marijuana. Uruguay is the first country to fully legalize the production, sale and distribution of the drug.
Under a controversial law passed last December, marijuana users who sign up for a national register are allowed to grow cannabis, buy it at a pharmacy or join a distribution club.
On the first day of registration for private growers, 10 people had signed up in the morning -- three in the capital Montevideo and seven in the South American country's interior, according to the newly created Institute for the Regulation and Control of Cannabis (IRCCA).
To sign up, would-be growers must go to a designated post office with an ID card and proof of residence.
Registration is free and users' names are kept confidential. The program is open only to adults who are Uruguayan citizens or permanent residents.
Growers are limited to six plants per home and maximum production of 480 grams (17 ounces) a year.
The first to register in Montevideo was Juan Vaz, spokesman for the Uruguay Association for Cannabis Studies (AECU).
"To me, being registered legitimates me instead of discriminating against me," he told journalists.
AECU estimates there are currently 30,000 to 40,000 cannabis growers in Uruguay.
Uruguay's leftist President Jose Mujica told AFP last month that direct sales to consumers would be delayed until next year because of difficulties implementing the new law.