Lithophyte

[2] Lithophytes that grow on land feed off nutrients from rain water and nearby decaying plants, including their own dead tissue.

It is easier for chasmophytes to acquire nutrients because they grow in fissures in rocks where soil or organic matter has accumulated.

Some wall plants even have 'wall' or 'muralis' as part of their common or scientific name such as wall-flower (Erysimum cheiri) or ivy-leaved toadflax (Cymbalaria muralis), which shows their long established relationship with these man-made structures.English HeritageLandscape Advice Note: Vegetation on Walls [4]Examples of lithophytes include many orchids such as Dendrobium and Paphiopedilum, bromeliads such as Tillandsia, as well as many ferns, algae and liverworts.

Lithophytes have also been found in many other plant families, such as, Liliaceae, Amaryllidaceae, Begoniaceae, Caprifoliaceae, Crassulaceae, Piperaceae and Selaginellaceae.

[5] As nutrients tend to be rarely available to lithophytes or chasmophytes, many species of carnivorous plants can be viewed as being pre-adapted to life on rocks.

Nepenthes sp. Misool growing as a lithophyte in Raja Ampat , New Guinea
Asarina procumbens , the trailing snapdragon, colonising a crevice in a Berwickshire sandstone church wall - just as it would a siliceous inland cliff in its native Pyrenees
Erysimum cheiri , the wallflower, growing out of the (brick) city wall of Louvain
National Trust plaque displayed on the wall of the wishing well at Waggoners Wells commemorating the composition of the poem "Flower in the Crannied Wall"