How well the skilful gardener drew
Of flow'rs and herbs this dial new;
Where from above the milder sun
Does through a fragrant zodiac run;
And, as it works, th' industrious bee
Computes its time as well as we.
How could such sweet and wholesome hours
Be reckoned but with herbs and flow'rs!
Carl Linnaeus, father of taxonomy, divides the flowering plants into three groups:
the meteorici, which change their opening and closing times according to the weather conditions;
the tropici, which change their opening and closing times according to the length of the day;
and the aequinoctales, which have fixed opening and closing times, regardless of weather or season.
Linnaeus notes in his Philosophia Botanica that if one possessed a sufficiently large variety of aequinoctal species, it would be possible to tell time simply by observing the daily opening and closing of flowers.
He comments, to the consternation of several local horologists, that his floral clock is so accurate that it
“could put all the watchmakers in Sweden out of business.”