"passion grew" is correct and usable in written English. You can use it whenever you want to indicate that someone's level of passion is increasing, such as: "As they talked, her passion grew until it was impossible to ignore.".
The passion grew as he got older.
The lanky yellow rose succeeded, and my passion grew.
The passion grew because I could see how isolated and vulnerable my new friends were.
As his passion grew, Sir Arthur, who coined the term micromosaics, wanted to see and learn more.
I hope the passion grows, along with the persistence to grow them.
The passion grows from the spirit of the game, its beauty, complexity and subtlety.
Becoming an ascetic, he remains willfully blind to the passion growing between his apprentice and his love-starved young wife.
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Claudia Letizia
Head Translator and Proofreader @ organictranslations.eu