Detectives in Naivasha on Thursday arrested 14 people who were found weeding a field of bhang.
The banned drug was valued at Sh27 million.
Directorate of Criminal Investigations (DCI) said the operation was conducted by a multi-agency team comprising Anti-Narcotics detectives and police officers.
Police acting on a tip-off from members of the public pounced on the suspects weeding the more than one-acre field of bhang at Kedong ranch.
Detectives have launched an investigation on how the suspects managed to plant a whole acre of bhang.
The 14 are in police custody and will be arraigned once investigations are completed.
Last September police in Thika arrested three men at a construction site in Ngoingwa Estate.
The three are reported to have been growing bhang, ostensibly for personal and commercial use.
The cannabis plants were planted in crates, a nursery, and several other containers.