Moss Garden

With a history that stretches back more than 470 million years, mosses are the oldest of land-based plants. These minute but hardy organisms have been shaping our planet for a long time.

The mysterious world of mosses unfolds in the Botanical Garden's European section, where you'll also find other native European mosses.

Preparations for creating a moss garden on the north slope of the old bastion and in the bastion moat started in 2011. Since the area overlaps with historical park grounds, the varied humidity and light conditions have combined to create a site that is favourable to many species of moss - the site is home to close to a quarter of Estonian mosses. The Botanical Garden's Moss Garden introduces mosses, the diverse world of moss plants and their role in ecosystems.

Those characteristically found on sandy soils and rich but thins soils grow on the level plateau, while the central part of the Moss Garden sustains lime-loving species, and the limestone wall provides convenient purchase to a variety of ferns. The puddles of water that mark the location of the old moat create an environment conducive to the growth of bogland mosses. This is also where one can find the peat moss (Sphagnum russow) named in honour of the one-time director of the Botanical Garden, the bryophytes researcher Edmund Russow (1841–1897).

The construction of mosses can be considered primitive, but enough to withstand the ravages of time. Their predominantly tiny growth is due to the limited ability of the tissues to conduct water - mosses lack the conductive zones characteristic of other plants. They also lack roots and the ability to store water. Moss leaves are mainly only one cell thick and dry out quickly. However, drying out does not necessarily mean that the plant dies.

The ability to put cells into dormancy and survive long periods of dryness is common to many moss plants. A good example is Tortula ruralis, which can often be found growing on roofs. The moss, which turns brown when dry, quickly regains its bright green colour after the rains and continues to grow even after prolonged droughts. Some species, such as Rhytidiadelphus triquetrus, which is found mainly on the lower slopes of Moss Garden in sagebrush communities, maintains its green colour even when dry.

Species that do not tolerate drying out are planted in ponds in the Moss Garden. The key species in our swamps – Sphagnum – can be found in a larger pond with acidic, low salinity water. Higher up, the nutrient-rich, alkaline-water lesser pond concentrates species such as Paludella squarrosa, as well as reaction-neutral species such as Conocephalum conicum.

In the surroundings of the pond, there is a rare species of Equisetum scirpoides and Polystichum braunii, which is found only once in Estonia.

In the central part of the Moss Garden, calcareous species are common on the limestone slopes. Here, Homalothecium sericeum, with its beautiful golden colouring, catches the eye, while Asplenium trichomanoides, a protected species, makes itself at home on the moraine.

In the lower part of the relief, on the steeper slopes, you can see species typical of the klint forests. Here you can see Cystopteris sudetica, which has been found in Estonia in only one place.

These small but tenacious organisms have changed the face of planet Earth beyond recognition. As the first terrestrial plants, mosses are responsible for the formation of soil decomposition processes, and it is easy at first glance to underestimate their contribution as oxygen producers and carbon fixers. Plant gas exchange processes have been a major driver of climate change for millions of years and continue to have a direct impact on climate change today.