Hydroponics shop owners and workers from across the Black Country and Birmingham were sentenced on Tuesday for helping others to grow cannabis.
They had been selling the hydroponics equipment needed to produce the class B drug, and were convicted following an extensive undercover police operation.
Cannabis equipment shop workers behind bars in West Midlands first
One of those behind the sting, Acting Detective Chief Inspector Tom Chisholm, said there is currently nothing in law to regulate this kind of hardware.
He said: "There is no legislation at the moment that prevents anyone selling hydroponics equipment.
"We wanted to test a hypothesis that they were going beyond just selling the equipment, and in the cases of the ones we convicted they were. I'm hoping having this sort of debate might kick start people into looking into legislation around this, but that's out of my hands."
The operation was launched in response to the number of this type of shop that seemed to be springing up across the West Midlands.
DCI Chisholm said: "We noticed that a lot of the cannabis factories we were raiding had equipment that can be bought from these kinds of places.
"So we wanted to test our hypothesis and see if these shops were actively promoting the growing of cannabis – it was an integrity test.
"We selected a few of these shops and sent in undercover officers, who spoke to the people working there.
"We had general conversations about setting up 'grows', and as a result the majority openly engaged with us, and spoke about things like crop cycles, profits from grows, and methods to avoid police detection."
In some cases, some of the shops even cross-referenced each other, and told officers where they might be able to buy cannabis seeds, for 'ornamental purposes'.
DCI Chisholm added: "From the content of the conversations, they were quite clearly talking about cannabis."
As a result, some of those involved with three hydroponics shops in the Black Country – Growpatch Ltd on Blackheath High Street, Extra Grow Hydroponics at Wednesbury Trading Estate, and Red Eye Jungle Shop in Stafford Street, Walsall – have now been convicted.
A 28-year-old man from Oldbury, who worked at a shop in Grow World, Bristol Road South, Northfield, was also jailed. All 11 who were convicted at Birmingham Crown Court on Tuesday had pleaded guilty to assisting others to commit an offence.