On Robin's recommendation, Morison became director of the Royal Gardens at Blois, Central France, a post which he subsequently held for ten years.

[1] In 1660, despite inducements to make him stay in France, Morison returned to England following the Restoration and became physician to Charles II as well as his botanist and superintendent of all the royal gardens with a salary of £200 per annum, and a free house.

At the time, classification focused on the habitat and medicinal properties of the plant and Morison's criticism of systems promoted by botanists such as Jean and Gaspard Bauhin caused some anger among his contemporaries.

[4] In 1669, he also published 'Hortus Regius Blesensis' by the newly revived University Press, it was a catalogue of the Blois garden to which Morison added the description of 260 previously un-described plants, although Richard Pulteney (A General View of the Writings of Linnaeus, 1781) disagreed and noted that they were only varieties and others were already described.

[5] In the preface to his Plantarum Umbelliferarum Distributio Nova (1672), Morison gave a definitive statement of the principles of his method and was the first person to write a "monograph of a specific group of plants", the Umbelliferae.