The council has found individuals selling cotoneaster, buddleia and an invasive succulent known as pig's ear. A commercial nursery was also found selling a variety of a wilding pine.

"It just keeps on growing." Gardener met with urgent warnings after sharing photos of relentless plant: 'Cutting it back ... won't stop it spreading' first appeared on The Cool Down.

Environment Southland has warned against backyard nurseries selling pretty, but banned, plants on social media.