This is killing me. When I was young I remember reading this book:
- female heroine
- young adult fantasy fiction
- need to draw? runes in the air or tattoo them to do certain spells
- opening scene young girl doing magic in a garden, runes/magic above her level and I believe her fire ball spell gets away from her and floats around.
- possibly a male character has a hidden island later in the book.
I know its vague, I apologize but my sister and I cannot remember any more than that and after 20 years, the book is lost in our childhood home somewhere.