In general:

Vegetation can stand in a dream for the obstacles which the dreaming artificially built before himself to obtain a growth process. So he can be hindered by thorny bushes in making headway. However, stinging nettles represent perhaps people who consciously confront the progress.

Psychologically:

While the obstacles which the dreaming constructs before himself can cause difficulties, on the other hand, the picture implies also lavish fullness and fertility, which can be granted to him. If you want to clear vegetation, possibly in a kitchen garden, can point to the fact that the dreaming clears what is no longer useful to him.

Spiritually:

Vegetation in the dream symbolizes fullness and growth possibilities at spiritual level.

* Please, see meaning of growth.