When the urge unearthed itself, Joan Mercer was at the sink washing dishes, her husband’s egg cup and her children’s cereal bowls. She flicked the soapsuds from her hands and crossed the kitchen, going out through the sliding doors and onto the wooden deck. There, she contemplated the garden. In the corner of the backyard, jonquils were blooming. But it wasn’t these that drew her over the lawn. It was the jacaranda tree. It was calling to her.