SOLVED. 90s book about a girl forced to help tend her grandma's garden? [s]

[Famine]

I used to have a book I read in the 90s about a girl who was forced by her parents to help her grandmother tend her garden in exchange for a favor. It was a novel, not a picture book, either YA or younger.

The cover was possibly white with a black cat, I think. I am Australian so it may have been an Aussie author!

[Kris]

Wolfrott, what's the tone - funny, serious, bittersweet, etc.?

Is this about learning an important lesson? A coming-of-age story?

Are there other characters in the story like siblings or friends?

[Famine]

I've just solved it myself this morning, was about to update this thread! :)

Tangles