It is widely believed that Nicholas Culpeper came from aristocratic origins and grew up in a family, owning land, which was a privilege denied to many in these years. Culpeper was highly influenced by his grandfather Reverend William Attersole, who was known to be an intellectual. He taught his grandson and it is assumed that he had high ambitions for the young Nicholas, including sending him to Cambridge, where the Attersole himself had once been educated. He was educated in Latin as well as Greek and it is believed that he read numerous books he found in his grandfather's library on astrology at early age. Further, it is assumed that there he also discovered William Turner’s Herbal, which apparently initiated his interest in medicine, plants and herbs. 
However, Culpeper's grandfather was not really amused when finding out about the boy's interests and soon restricted his readings to the Bible. He was sent to Cambridge at the age of 16 in order to study theology and to become a Church Minister in later years. Well, this was the initial plan, but the teenager soon decided differently and read the medical works of Hippocrates and Galen instead. On this day, Culpeper is quite well known as the 'rebel' scientist, who next to his studies apparently began drinking and smoking to compensate his frustration on his grandfather. Due to a secret relationship Culpeper's with heiress Judith Rivers which turned into quite a scandal, the student left Cambridge. However, Reverend Attersole organized an apprenticeship for his grandson with the Master Apothecary, Daniel White and soon after abandoned his grandson. He was apprenticed for over seven years and catalogued various medicinal herbs in this period. When he was finally able to abandon his ties with White, Culpeper continued his 'career' in London's poorer areas and soon gained a reputation as the healer of the poor. It is assumed that he charged only very little or nothing at all for his services as he highly sympathized with their struggles. [1,2]
It is further assumed that Culpeper had ambitions to reform the medical system, questioning traditional methods and exploring new ways of healing. A key factor in order to do so was the systematization of the use of herbals. His focus moved from tradition to reason and began combining plants and diseases. His 'Complete Herbal' is known to have had a great influence on medicine in the western world. The success is also due to the fact that he managed to translate numerous documents discussing medicinal plants from Latin into English. 
At yovisto, you may be interested in a Gresham Video Lecture on 'The Hidden Face of British Gardening' by Prof. Dr. Sir Roderick Floud.
References and Further Reading:
- Sir Patrick Manson - The Father of Tropical Medicine
- All articles related to medical science