Level
3rd
Casting Time
Special *
Range/Area
150 ft.
(100 ft. )
Components
V, S
Duration
Instantaneous
School
Transmutation
Attack/Save
None
Damage/Effect
Control
This spell channels vitality into plants. The casting time you use determines whether the spell has the Overgrowth or the Enrichment effect below.
Overgrowth. Choose a point within range. All normal plants in a 100-foot-radius Sphere centered on that point become thick and overgrown. A creature moving through that area must spend 4 feet of movement for every 1 foot it moves. You can exclude one or more areas of any size within the spell’s area from being affected.
Enrichment. All plants in a half-mile radius centered on a point within range become enriched for 365 days. The plants yield twice the normal amount of food when harvested. They can benefit from only one Plant Growth per year.
* - Action (Overgrowth) or 8 hours (Enrichment)
Tonight, my party will attempt to Enrich the vines at Wizard of Wines. 8 hours to cast a spell while in Barovia is not going to be as easy as it sounds...
How'd it go?
Strahd rolled up and salted the vines before flipping the party the middle finger and mist-ing off.
How long does the overgrowth last?
Basically indefinitely. Or, at least, until someone takes the time to undo it by trimming the plants away, burning them, etc.
Because the spell's duration is Instantaneous, and there's no duration specified for that specific effect, I think we're meant to infer that the "overgrowth" is sort of a magical stimulation of the plants' innate ability to grow. The growth is natural, just magically accelerated, so there's no lingering magical effect that "ends" or can be dispelled.
Your CoS game is way different from the one I'm in. Our first decision was literally "we wander aimlessly" because we didn't want to go to the town.