John Gerard was born in Nantwich, England in 1545. He received only rudimentary schooling, and was apprenticed as a barber-surgeon around the age of seventeen. Although Gerard would later claim to have learnt much about plants from travelling to distant corners of the world, his actual travels appear to have been limited. The only surviving evidence is of a single trip abroad, possibly as a ship’s surgeon, on a merchant ship sailing around the North Sea.

While studying in London, Gerard became interested in plants and began a garden near his cottage in Holborn, London. Both the garden and its owner soon became popular, and Gerard was often presented not only with rare plants and seeds from different parts of the world but also with offers to supervise the gardens of noblemen. In 1577, aged 22, Gerard began to oversee the London gardens of William Cecil, 1st Baron of Burghley. He worked diligently over the next two decades, and by 1595 had become a member of the Court of Assistants in the Barber-Surgeon's Company. A year later, Gerard published a list of rare plants, mostly acquired from the New World, which he had cultivated in his own garden at his home. One of these was a plant he misidentified as the Yucca. Though it failed to bloom in his lifetime, to this day Yucca bears the name Gerard gave it. A copy of his 1596 lists is viewable today in the British Museum.

In 1597, Gerard shot to fame with the publication of his massive (1,480 page) Great Herball, or Generall Historie of Plantes. The heavily illustrated work was the most widely circulated English-language botany book in the seventeenth century. Except for the additions of a number of plants from his own garden, however, Gerard's book was largely a translation of Rembert Dodoens Herbal of 1554. A couple of decades after his death, his book was corrected and expanded (to about 1700 pages), which strengthened the book's position over subsequent decades. Great Herball, or Generall Historie of Plantes established Gerard as one of the founders of botany, despite his limits in terms of technical knowledge and scholarly prowess (Gerard was dogged by accusations of plagiarism in the wake of his publishing success).

In 1597, Gerard was appointed junior warden of the Barber-Surgeons, and in 1608, master of the same. He died around 1611 at his home in Holborn, London. The Herball remains influential to this day; substantial portions of it were reprinted in 1927 and 1964, and it remains a popular work for those interested in folklore and plant remedies.