In terms of bringing both a chemical and spiritual understanding to the alchemy of plants, we recommend the following books/resources to thoroughly understand alchemy and the wheel work of nature that drives these manifestations of nature.
We have provided links where you can download these via PDF free of charge.
Plant Alchemy by Manfred Junius
A great guide that introduces all forms of spagyric preparation and does a good job incorporating different spiritual philosophies regarding alchemical preparation. Also lab based and informative.
The Alchemist's Handbook by Frater Albertus
A true gold mine of information. We have adopted a lot from Frater Albertus' work with chapter titled 'The Herbal Elixir.' Very lab based and meant for well adapted spagyricists.
Spagyrics (A Practical Course in Plant Alchemy) by Jean Dubuis Book 1 & 2
A good introduction to spagyrics incorporating more spiritual philosophy.