Couchman met up with the man on the outside and supplied him with the drugs.
When the mule returned to prison, he was searched by Corrections staff and taken to Whanganui Hospital for an internal examination, leading to the discovery of the drugs.
But it wasn't the only time Couchman's prison calls were intercepted and reported to police.
The month prior to the drug smuggling, Couchman discussed with an inmate over the phone plans to sell cannabis.
Couchman said he had about a pound of weed in the boot of a car at a Stratford property and agreed to sell an ounce of the drug and use the proceeds to top up the inmate's "account".
A later search of Couchman's house saw police discover 41g of cannabis.
In a further incident, in March this year, Corrections intercepted another call in which Couchman told an inmate he had a firearm at his house and a large amount of cannabis.
A search of his property turned up a .223 firearm with an attached suppressor and a hoard of ammunition.
Couchman said he had the gun for protection but as the respondent of an active protection order he is prohibited from possessing or owning a firearm.
Now in custody himself, he appeared in New Plymouth District Court on Friday for sentence on 14 charges, some of which stemmed from the offending brought to light by the phone calls.
In addition to seven drug-related charges, he faced breaches of a protection order, unlawful possession of a firearm and ammunition, and three driving-related charges.
Judge Tony Greig said Couchman has an extensive list of previous convictions and had been assessed as a high-risk of reoffending.
But he has also expressed a desire to change, Judge Greig said.
"I accept that you genuinely do want to make some changes, you just seem to have no idea how to go about it."
Following reductions for that "genuine desire to rehabilitate", totality, guilty pleas, and time spent on electronically-monitored bail, Couchman was jailed for three years and three months.
He was also disqualified from driving for 12 months and an order for destruction of the firearm and drugs was made.
If truly sincere about changing the course of his life, Couchman would now have to prove himself to the Parole Board, Judge Greig said.