When the Entangle spell ends, do the plants disappear after they “wilt away”?

The description of the entangle spell reads:

Grasping weeds and vines sprout from the ground in a 20-foot square […]

When the spell ends, the conjured plants wilt away.

Does “wilt away” mean they just wither and die like regular plants, and so the ground is covered in dead vegetation to mark where the spell was cast? Or do they fully disappear, as magically as they first appeared?