Pre-Linnaean Systems:
– Theophrastus classification (c. 300 BC)
– Dioscorides classification (c. 60 AD)
– Systema Naturae, 1st edition, 1735
– Adanson system, 1763
– de Jussieu system, 1789
Linnaean and Post-Linnaean Systems:
– Species Plantarum, 1753
– Genera Plantarum, 1737 (1st ed.)
– Lindley system, 1830
– Bentham & Hooker system, 1862–1883
– Baillon system, 1867–1894
Post Darwinian (Phyletic) Systems:
– Eichler system, 1883
– Engler system, 1887–1915
– Bessey system, 1907
– Wettstein system, 1901-1908
– Rendle system, 1904, 1925
Continued Evolution of Systems:
– Lotsy system, 1907–1911
– Hutchinson system, 1926–1934
– Kimura system, 1956
– Benson system, 1957
– Melchior system, 1964
Modern Taxonomic Systems:
– Takhtajan system, 1966
– Cronquist system, 1968
– Dahlgren system, 1975
– APG system, 1998
– Angiosperm Phylogeny Group classification, 2003
This list of systems of plant taxonomy presents "taxonomic systems" used in plant classification.
A taxonomic system is a coherent whole of taxonomic judgments on circumscription and placement of the considered taxa. It is only a "system" if it is applied to a large group of such taxa (for example, all the flowering plants).
There are two main criteria for this list. A system must be taxonomic, that is deal with many plants, by their botanical names. Secondly it must be a system, i.e. deal with the relationships of plants. Although thinking about relationships of plants had started much earlier (see history of plant systematics), such systems really only came into being in the 19th century, as a result of an ever-increasing influx from all over the world of newly discovered plant species. The 18th century saw some early systems, which are perhaps precursors rather than full taxonomic systems.
A milestone event was the publication of Species Plantarum by Linnaeus which serves as the starting point of binomial nomenclature for plants. By its size this would qualify to be on this list, but it does not deal with relationships, beyond assigning plants into genera.
Note that a system is not necessarily monolithic and often goes through several stages of development, resulting in several versions of the same system. When a system is widely adopted, many authors will adopt their own particular version of the system. The Cronquist system is well known for existing in many versions.