Botanical development in colonial India was intertwined with colonial expansion, explorations and institutionalisation. This paper looks at the contribution of the so called ‘Father of Indian Botany’ William Roxburgh who contributed to the formation of the botanical knowledge and institutional systems in India. Roxburgh's activities in plant economy, classification, documentation and research set the scene for systematic botanical research in the late 18th and early 19th centuries. His work had an impact on the later creation of scientific institutions like the Botanical Survey of India. The paper examines the role of botanical science in the service of empire, as a means to the extraction of resources, improvement of agriculture and control of administration. It also reminds the reader of the long-term effects of colonial botany on the scientific institutions of India. The study makes the point that botany was a key factor in combining science with imperial government and institutionalization.