Book has masking tape with 50 written on it.  See pics.

The "Better Homes and Gardens House Plants Book" is a vintage book designed for garden plant lovers. Written by the editors of Better Homes and Gardens, this nonfiction book focuses on house plants and indoor gardening. With beautifully illustrated pages, this book serves as a comprehensive guide for adults interested in enhancing their living space with greenery. Published by Vintage Books, this book provides tips, advice, and inspiration for plant enthusiasts looking to bring more beauty and life into their homes.