The fact that the Rodopi Mountain Range was not covered with ice during the Pleistocene period makes the region a botanical paradise of flora species variety. Almost 60% of the European flora species can be met here and it is the refuge of 211 rare or endangered with extinction species. Fifteen (15) of them are remnants of the tertiary period, 40 are endemic species of the Balkan Peninsula and 50 species are endemic of the Rodopi Mountain Range which cannot be found anywhere else in the world. In total it is estimated that the number of the flora species and subspecies is over the 1000 taxa (1115 recorded taxa from which the 827 are species and the 288 are subspecies). (References: Environmental Study of the Rodopi Mountain Range)

The main vegetation zones with the individual forest ecosystems which exist in Greece can be found here. Specifically inside the RMRNP can be found:

Quercetalia pubescentis (Pic. 5): It comprises the larger volume of the forests of the region and it is mainly consisted of Oak ecosystems. In this zone can also be found ecosystems of evergreen and deciduous species (Chestnut, Hornbeam, Kermes Oak, etc.).
Fagetalia (Pic. 6): This zone is mainly represented by ecosystems of Beech and European Black Pine.
Vaccinio – Picetalia (Pic. 7): The main species are Scots Pine, Spruce and Birch which possess 17.5% of the forest of the region.
Alpine and subalpine zone (Pic. 8): This zone is over the treeline (in Greece these treelines are usually made by humans). This zone is consisted of meadows and herbaceous vegetation with sporadic bushes

It is worth to be mentioned that the western greek Rodopi Mountain Range is the southern boundary of expansion of Spruce where it appears in an extensive area in the unique Spruce forest of Elatia.

Following there are indicative tables of flora species and subspecies of the RMRNP:

Pteridophyta (Adiantaceae - Sinopteridaceae)

Gymnospermae (Cupressaceae - Pinaceae)

Monocotyledoneae (Alismataceae - Dioscoreaceae)

Monocotyledoneae (Graminae)

Monocotyledoneae (Iridaceae - Typhaceae)

Dycotyledoneae (Corylaceae - Caprifoliaceae)

Dycotyledoneae (Caryophyllaceae)

Dycotyledoneae (Celastraceae - Compositae)

Dycotyledoneae (Convolvulaceae - Cruciferae)

Dycotyledoneae (Linaceae - Polygalaceae)

Dycotyledoneae (Rosaceae)