Usually I feature a moss in each newsletter but this time I have Marchantia on my mind – a liverwort. Sometimes liverworts are mistaken for mosses but this most common worldwide liverwort is easy to distinguish. A thallose liverwort with BIG leaves (at least big for bryophytes), Marchantia polymorpha can be found in all types of climates from arctic regions to tropical forests. Instead of the typical style moss sporophytes, this “moss cousin,” has reproductive “umbrellas”. Gemmae cups are clearly visible on the round-lobed leaves illustrating another reproductive function. Marchantia p. has a deep, brilliant green color that almost glows in the landscape.
If we interpret scientific observations of this liverwort in its natural surroundings and habitats, we once again discover how yet another bryophyte could be valuable as a preferred horticultural choice for solving environmental issues of erosion control and restoration of disturbed habitats. Documented research indicates that the rhizoids of Marchantia intertwine and securely attach to soil substrates in tight mats. Erosion control can be achieved by purposefully introducing this fast-growing liverwort described as an early “invader” of fire sites. In nature, it is considered an early succession plant and in several years other vascular plants move in to dominate the area as these liverworts help rebuild the soil. However, sometimes the tight mats hamper new growth of other seedlings. It can thrive on disturbed soils high in heavy metals such as lead, zinc and chelated copper but regular copper hampers growth. It prefers subcalcareous soil conditions (pH 6.0) under full sunlight.
Now, the real reason Marchantia is on my mind is that I’m having great success introducing this liverwort as a lawn option. Since it is considered a “weed” because of its fast-growing properties, I decided to try it out in my moss lawn experiments. Rescued from an urban greenhouse where it was considered a bother, this liverwort was planted last fall and exposed to snow and freezing temperatures this past winter. Now, in May, it is displaying new “umbrellas” and seems to be spreading faster than some other bryophyte types. It is planted in a partial shade/mainly sunny spot directly on landscape fabric weed barrier with only the soil that came attached to the colony. As part of my typical watering regime, when it doesn’t rain, these liverworts receive supplemental overhead watering three times a day for 5 minutes each session. I might have to change my own mind about the value of liverworts in garden applications and start saying… Go Green With Mosses… and Liverworts!