The most common and most likely answer to this crossword clue is the 6 letter word NETTLE
I've seen this crossword clue in Financial Times
N
E
T
T
L
E
More clues leading to the result NETTLE
- Get annoyed with what might appear on waste land
- The rental’s high leading to complaint
- A stingy type to annoy!
- Common weed bug
- Decide to have new leader for plant
- Prove irritating as a weed
- Bug caught, then let loose
- The bottom line – settle 50%, that’ll annoy
- It grows painful to touch
- The web let fly, a cause of some irritation
Buddy explains!

The straight part
We know that "Prove irritating/a weed" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case prove irritating/a weed = nettle.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does NETTLE mean?
NETTLE noun- Any plant whose foliage is covered with stinging, mildly poisonous hairs, causing an instant rash.
- Certain plants that have spines or prickles:
- Certain non-stinging plants, mostly in the family Lamiaceae, that resemble the species of Urtica:
- Loosely, anything which causes a similarly stinging rash, such as a jellyfish or sea nettle.
- Of the nettle plant and similar physical causes, to sting, causing a rash in someone.
- To pique, irritate, vex or provoke.