The year 2009 marks the bicentenary of Charles Darwin’s birth and 150 years since publication of his theory of evolution, the seeds of which were sown while he was Naturalist during the voyage of the Beagle. Darwin’s botanical observations during that five-year long trip and his thousands of experiments with plants after his return to England provided much of the evidence he used to develop and substantiate his theory. Botany became a time-consuming passion that spanned topics as diverse as plant physiology, plant breeding and domestication, pollination biology, plant morphology and ecology. This paper provides an overview of his experimental work on plants, carried out at his home, Down House, using household items as equipment and working with hundreds of different species from across the flowering plant kingdom. Darwin communicated the results of his work in scientific and popular journals and in seven books, the last of which was published when he was 74 years old. In his autobiography, Darwin attributed his success as a scientist to his love of science, unbounded patience, industry in observing and collecting facts, invention, and common sense. Darwin remains an inspiration for the budding scientists of the 21st century.