Philip Miller FRS (1691 – 18 December 1771) was an English botanist of Scottish descent.
Born in Deptford or Greenwich Miller was chief gardener at the Chelsea Physic Garden from 1722 until he was pressured to retire shortly before his death. According to the botanist Peter Collinson, who visited the physic garden in July 1764 and recorded his observation in his commonplace books, Miller "has raised the reputation of the Chelsea Garden so much that it excels all the gardens of Europe for its amazing variety of plants of all orders and classes and from all climates..." He wrote The Gardener's and Florists Dictionary or a Complete System of Horticulture (1724) and The Gardener's Dictionary containing the Methods of Cultivating and Improving the Kitchen Fruit and Flower Garden, which first appeared in 1731 in an impressive folio and passed through eight expanding editions in his lifetime and was translated into Dutch by Job Baster.
Miller corresponded with other botanists, and obtained plants from all over the world, many of which he cultivated for the first time in England and is credited as their introducer. His knowledge of living plants, for which he was elected a Fellow of the Royal Society, was unsurpassed in breadth in his lifetime. He trained William Aiton, who later became head gardener at Kew, and William Forsyth, after whom Forsythia was named. The Duke of Bedford contracted him to supervise the pruning of fruit trees at Woburn Abbey and the care of his prized collection of American trees, especially evergreens, which were grown from seeds that, on Miller's suggestion, had been sent in barrels from Pennsylvania, where they had been collected by John Bartram. Through a consortium of sixty subscribers, 1733–66, the contents of Bartram's boxes introduced such American trees as Abies balsamea and Pinus rigida into English gardens.