Eu me pergunto se poderia ser The Mind Pool, de Charles Sheffield, publicado em 1993.
A flor foi projetada por um cientista chamado The Margrave aka Fujitsu:
The Margrave stared at them gloomily and nodded. He closed the door and triple-locked it, then turned and pressed a light switch. At the other side of the room sat a bulbous plant, five feet high and about two feet across. When the light went on the leaves of the swollen upper part began to open. In less than thirty seconds a single vast flower was revealed. Its central part resembled a human face, with pink cheeks, curved red mouth, and blind blue eyes. After a few moments, the mouth opened. A thin, beautiful tone came forth, a crystalline, pure soprano singing a wordless lament. The song continued and broadened, from a simple theme through to a complex coloratura embroidery.
As sondas instelares são chamadas de Morgan Constructs. Eles foram projetados para explorar o universo, mas algo deu errado e eles se mostraram hostis a todas as formas de vida. Havia dezessete deles originalmente, mas quatorze foram destruídos em sua tentativa de fuga, deixando os três que você mencionou, embora dois foram posteriormente mortos. O restante do livro é sobre a busca pelo último constructo.