How do you cast the spell herbivicus on Harry Potter for the PSP?

In the Harry Potter and the Goblet of Fire video game for the PSP, to cast the spell Herbivicus on Harry Potter, you need to press the corresponding button combination on the PSP controller. The specific button combination may vary depending on the game's controls configuration. Make sure to consult the in-game spell list or instruction manual for the exact input sequence to successfully cast Herbivicus on Harry.