Answer:
It's like food but water kills it. What is it?
Useful tool for who in darkness dwell. Within you, corrupting like a deadly spell.
When they are caught, they are thrown away. When they escape, you itch all day.
Being able to interpret the letters on this screen proves that you have this quality.
Grows from the ground, bushes and grass, leaves of yellow, red and brow, unruly plants, get the axe, trim the hedge back down.
What language does a billboard speak?