General terms:
* Overgrown: This is a general term for an area that has been allowed to become covered in plants.
* Jungle: This term implies a dense, tangled growth of tropical plants.
* Thicket: This describes a dense growth of bushes or small trees.
* Undergrowth: This refers to the low-growing plants and vegetation that cover the ground beneath taller plants.
More specific terms:
* Brush: This refers to dense, tangled growth of shrubs and small trees.
* Weeds: This specifically refers to unwanted plants that grow in cultivated areas.
* Flora: This is a scientific term for all the plant life in a particular area.
* Vegetation: This is a general term for all the plants in a particular area.
Figurative terms:
* Green labyrinth: This is a poetic way to describe a place where plants are so thick they form a maze.
* Botanical wilderness: This emphasizes the untamed and wild nature of the plant growth.
The best word to use depends on the specific situation. For example, if you're talking about a neglected garden, "overgrown" might be the best choice. If you're describing a tropical rainforest, "jungle" would be more appropriate.