June views the world in colour and bloom. She is a keen horticulturist and an amateur arborist, and she can name every flower species beginning with the letter J. She knows a lot about garden management and soil cultivation. But what she doesn't know a lot about, is people.

When her mother dies unexpectedly and their home is repossessed, June decides to journey south to find her secondary caregiver who she has not seen since she was an infant. However, June's biological father does not want to be found, nor does he want to be reminded of those turbulent times up north with her mother. Panicked and confused, he turns her away, not wanting to jeopardise his London life and his new family, who he lives with in a big redstone townhouse in Notting Hill in a garden filled with white roses and lemon thyme, on a street lined with Japanese Dawn Redwood trees.

With nowhere else to go and without her father knowing, June moves into the yellow shed in his garden where she can spend her days once again surrounded by colour and bloom. There, she reluctantly forges a new friendship with her ten-year-old half-brother and the family dog, who keep her residence in the garden shed a secret, and over the course of a balmy summer in London she realises that this child is the only one who's ever really understood her.

As the summer blooms wither and autumn sets in, June is forced to both process the differences that stop her from maintaining social relationships with others, and the death of her mother if she ever stands a chance of connecting with her father, and with herself.