The year-round beauty of bryophytes appeals to many gardeners yet there are outstanding environmental reasons for choosing mosses.
It's not just “green” rhetoric when mosses are touted as eco-friendly. Indeed, their botanical characteristics have significant implications in a variety of horticultural applications. As we embrace approaches to sustainability, mosses offer advantages and solutions.
Myths abound about mosses which cloud the real facts. Indeed many mosses make great choices for shady spots with inferior soils where nothing else will grow. However, there are bryophyte choices for sunny exposures as well. Our options continue to expand as we examine bryophyte-specific solutions following right place, right plant guidelines. Mountain Moss Enterprises is conducting research and field tests to begin documenting bryophyte types that will be suitable for green roofs and moss lawns.
Imagine a world with green roofs that are truly green year-round or a green lawn that never needs to be mowed?
Green roofs are gaining supporters around the world. In fact, there is considerable longitudinal research on their advantages available from Europeans leading the way for decades. While sedums have been a preferred plant choice, mosses could be a substitute or a complimentary plant choice. In fact, even if not intentionally introduced, mosses are finding their own way onto green roofs. Where Mountain Moss is located, we already have mosses growing naturally on our asphalt and wood shake roof shingles. Having identified several types of mosses that have potential for green roofs, Mountain Moss has been conducting research to document growth patterns. Since bryophytes have no roots, just rhizoids, the required soil depth is significantly reduced. Engineering concerns for weight load are virtually eliminated.
Amazingly, once established, bryophytes can withstand high winds and hold to their substrate. Certain mosses will tolerate extremes in temperature and periods of intense heat. You don't necessarily need a northern exposure either. Mosses won't experience a dormant season like other flowers and plants that die back in freezing weather. The green appeal of hardy mosses will continue throughout all seasons, even in the winter months in harsh climates. And, mosses sure feel better to your feet than sedums if you really want to enjoy your green roof as a living space. Yes, you can walk on mosses. Moderate foot traffic doesn't damage them at all.
By creating moss lawns as an alternative to grass lawns, our environment would greatly benefit. Mosses require no chemicals typically used to maintain grass such as fertilizers, pesticides or herbicides. That means no groundwater contamination. Yet, the positive impact of eliminating the need for mowing has even greater implications for air quality. Fossil-fuel lawnmowers have no emission controls so pollution is significant especially when you multiply the millions of hours used in maintaining grass lawns in America. Just one hour of mowing with a gas-powered mower equals 43 hours of driving around in an inefficient vehicle. Even the benefit of alternative energy-efficient cars is negated if you still mow grass each week.
1 hour mowing = 43 hours driving inefficient vehicle
Botanically speaking, the fact that mosses have no cuticle and absorb water quickly means that they offer water filtration solutions for controlling storm water. Instead of water rushing through vegetation, mosses absorb water through their leaves slowing the flow and allowing rain to reach the groundwater table gradually. In terms of erosion control, there are several bryophyte types that are “root fakers” and will grow on sunny hillsides with steep inclines.
The tiny rhizoids of other mosses allow them to attach to vertical surfaces such as stone or concrete walls. Mosses offer many eco-friendly solutions in urban environments including reducing the heat index and for filtering rainwater run-off.
Sustainable approaches to landscaping yield more moss opportunities as we continue to create rain gardens as another storm water solution.
Native restoration projects emphasize the advantage of indigenous plants with mosses adding that final touch of subliminal appeal.
Moss instead of mulch offers better water filtration for thirsty vascular trees and plants while still providing a desirable insulating factor. Unlike bark mulches and pine needles, mosses won't have to be replaced each season, and beside, wouldn't you rather see green under your azaleas instead of brown?