The French printmaker François Houtin (1950- ) is an artist whose work has been devoted almost exclusively to the depiction of imaginary gardens.
Also an interesting blog: bibliodyssey.blogspot.com, introduced by Mr Aitch of Il Giornale as:
I’m grateful to Peacay, of Bibliodyssey renown, for introducing me to the work of this artist, nicely described by his friend and collaborator Gilbert Lascault as ‘the printmaker-gardener, the draughtsman-nurseryman, the demanding dreamer, the landscape artist, and the arboriculturalist-etcher.’
Here is another superb post from Bibliodyssey:
German naturalist Johann Christian Daniel von Schreber (1739-1810) trained as a physician and went and studied botany in Sweden under the great Carolus Linneaus. He would eventually edit one of Linneaus’s publications and he also included the Linnean binomial species naming system for the first time for some of the animals depicted above.