They are apparently semi-sentient and prehensile, being able to instantly coil around anything and anyone nearby. (Similar to Strangle Weed.) Their official description attributes this to their friendly disposition, but it is implied that the Groovy Vines use this as a foraging tactic, holding prey until it dies to ensure that it enriches their roots.
The Groovy Whip is made from Groovy Vines, and retains their unnatural properties.
The most friendly of all plants in Ninjago, Groovy Vines welcome you with open arms and never let go.