The most common and most likely answer to this crossword clue is the 7 letter word RAGWEED
I've seen this crossword clue in The Guardian
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More clues leading to the result RAGWEED
- Tease feeble individual, one undesirable in bed?
- Wager lost with pressman finding growth
- Plant that’s crimson gets weak in time when secluded
- First person in collective was angry about threat to crops?
- We raged about plant inducing hay fever
- Scold daughter about tiny plant that causes hay fever
- Got angry about case of wastage and growth
- Shred small date plant
- Allergen was out of control around our group
- Allergen was wild, engulfing our group
Buddy explains!

The straight part
We know that "plant inducing hay fever" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case plant inducing hay fever = ragweed.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 RAGWEED mean?
RAGWEED noun- A plant of the genus Ambrosia. These weeds are particularly noted for producing pollen which people with hay fever are allergic to.