Cannabis smokers in Switzerland will soon be allowed to grow up to four marijuana plants each at home to stop them buying drugs on the black market. Four people sharing a house can grow up to 16 plants - but only if each person tends to their own crop. The deregulation of Switzerland's already lax cannabis laws has been agreed by four neighbouring regions in the French-speaking part of the Alpine country. (See also: Les cantons veulent autoriser quatre plants de cannabis par personne)