Smoking cannabis is now legal for over-18s in Germany, after new laws for personal possession came into effect.
As of 1 April, adults in Germany are allowed to carry up to 25g of dried cannabis on them and cultivate up to three marijuana plants at home.
The new laws followed a heated debate about the pros and cons of allowing easier access to the drug.
The government says decriminalising weed will hit the hidden market, and reduce the spread of contaminated cannabis, thereby protecting young people. But there has been criticism about the possible impact on youths.
“From our point of view, the law as it is written is a disaster,” Katja Seidel, a therapist at a drug addiction centre in Berlin, the Tannenhof Berlin-Brandenburg, told Agence France-Presse (AFP).
“Access to the product will be easier, its image will change and become more normalised, especially among young people,” Seidel said, adding that she expected to see an increase in cannabis use “at least initially”.
Cannabis consumption by anyone under 18 will continue to be illegal.
The new legislation also has some safeguards to protect young people, including a ban on smoking cannabis within 100 metres (328ft) of a school, kindergarten, playground or sports centre.
Germany’s health minister, Karl Lauterbach, has promised a major campaign to educate young people about the health risks and boost prevention programmes.
However, the planned media campaign hasn’t convinced critics. “It doesn’t resonate with them, it will never work,” said Boris Knoblich, a spokesperson for the Tannenhof Berlin-Brandenburg organisation. “What works is someone who goes in, talks to them over a coffee, without a teacher there,” he said.
The federal centre for health education, linked to the health ministry, told AFP it will “assume its responsibility by expanding its prevention offers”.
The southern state of Bavaria meanwhile is testing an online training course for teachers on how to approach the topic in the classroom.
According to official statistics from 2021, 8.8% of adults in Germany aged 18-64 said they had consumed cannabis at least once in the preceding 12 months.
Among people aged 12 to 17, that number rose to nearly 10%.
The government has said previously that many users rely on the drug for medicinal reasons and that the new law will also improve the quality of cannabis consumed by growing numbers of young people.
Observers from around the world will be closely watching how the law works in practice in Germany.
With Kate Connolly in Berlin and Agence France-Presse