Living organisms continually change. The cause of the latest great change was the warming 12 thousand years ago, where the tundra vegetations of the Ice Age was, step by step, replaced by forest. The Adršpach Rock area was originally covered with primeval forest consisting of beeches, firs, pines, spruces, sycamores, birches and other species of trees. Of all the species, only the relict pines have persisted up to these days. Spruces were found much less here than today, it grew especially in dark and damp gorges. The first growth was, with time, artificially changed into spruce monocultures which showed to be less resistant to various adverse influences. Now, foresters try to increase the proportion of deciduous trees to make the woods better balanced and more resistant.

There are 11 "memorial trees" registered within the Broumovsko Protected Landscape area. One of them is the linden tree in the village of Horní Adršpach near house No. 31. Its age is approximately 300 to 400 years, the height is 24 metres (77 ft.) and circumference 670 centimetres (263 inches).

Within the national park, more than 250 species of bryophytes and around 400 species of vascular plants can be found. The relatively low number of plant species is due to the siliceous subsoil low in nutrients. The most interesting plant species can by found in deep gorges and slot canyons the climate of which correspond to higher mountain elevations. In the middle of the rocks, along the creeks stretch narrow strips of vegetation with Athyrium distentifolium. You can find here for example Cicerbita alpina or Viola biflora, Homogyne alpina and many others. A beautiful and rare representative of the peat plant communities found here is Ledum palustre. Abundant in quantity, you can also find snowflakes (Leucojum vernum) along creeks and in spring or swampy areas. Meadow horsetail (Equisetum pratense) can be found in places along the Metuje River. There are also a couple of species that do not originate from this area, e.g. Gentiana asclepiadea and especially Doronicum austriacum which has quickly sp read in the last few years. In addition, some other interesting plants can be found at the edge of the park such as several species of orchids, Turk's-cap lily and others.

Bryophytes
The bryophytes found in the area are those species which can grow on acidic subsoil low in nutrients. The most interesting species grow in deep and narrow gorges in the "rock town" where there is distinctive temperature inversion. Very cold places found here and there within the park are suitable for a series of alpine bryophytes which could not otherwise grow in such low elevations. They are just the coldest and shadowy gorges and slot canyons where the most noteworthy species of bryophytes are found: (Dicranodontium asperulum) and (Tetradontium repandum), on the rock walls (Polytrichum alpinum), (Oligotrichum hercynicum), (Pohlia drummondi) and (Rhizomnium pseudopunctatum) on the ground..
In a shady narrow gorge in the heart of the "rock town", a typical peatland species of (Mylia anomala) is found. (Dicranum sendtneri)– another interesting plant found in the rocks is considered to be the local endemic species.. A very rare species is (Tayloria tenuis) growing on decaying organic matter. Its occurrence has been confirmed in this area after nearly one hundred years. There can be found 17 species listed in the "Red List of Bryophytes" in the area.
In 1964, botanists found the first occurrence of Orthodontium lineare – an invasion species – in the territory of the Czech Republic. This bryophyte originating from the southern-hemisphere found for the first time in Europe (England) in 1911 has since then been spreading to the east. Nowadays, it can be found in 140 sites in the Czech Republic, especially in sandstone rock areas where it is very abundant.