Blight

A creature that you can see within range makes a CON saving throw, taking 8D8 Necrotic damage on a failed save or half as much damage on a successful one. A Plant creature automatically fails the save.

Alternatively, target a nonmagical plant that isn't a creature, such as a tree or shrub. It doesn't make a save; it simply withers and dies.

Using a Higher-Level Spell Slot: The damage increases by 1D8 for each spell slot level above 4.