Almost every potted plant you purchase is grown in a soil mix that contains peat moss, and the majority of bagged potting soils available also include it. Gardeners often buy peat moss to enhance their potting soil blends and it’s particularly favored for container gardening of flowers and edibles due to its moisture-retentive properties. Despite its widespread use and benefits in the gardening world, peat moss has become a contentious issue within the industry due to concerns about its sustainability. This article will delve into the drawbacks of using peat moss and explore more sustainable alternatives for your gardening needs.
:max_bytes(150000):strip_icc()/Peat-Moss-2-83eb6d562b6e43a68e77e359db7dba33.jpg)
A gardener prepares a pot for planting, using a potting mix that likely contains peat moss, highlighting its common use in home gardening.
What Exactly is Peat Moss?
When gardeners refer to peat moss, especially in North America, they are typically talking about sphagnum peat moss. Sphagnum moss is a type of moss renowned for its exceptional absorption capabilities. Remarkably, it can absorb up to 20 times its dry weight in water, functioning much like a natural sponge. Sphagnum moss thrives in damp, tundra-like environments, with the majority of peat moss used in the United States being harvested from peat bogs located in northern Canada. As sphagnum moss decomposes in these bogs over time, it gradually transforms into the peat moss that is widely utilized in gardening.
The Gardener’s Ally: Uses of Peat Moss
Potting mixes designed for container gardening face a dual challenge: they must provide adequate drainage to prevent root rot, while also retaining sufficient moisture for plant hydration. Peat moss offers an effective solution to this problem. Linda Chalker-Scott, a respected horticulture expert, describes peat moss as “a marvelous substance.” She explains that its effectiveness lies in its ability to act as countless tiny sponges within the soil. These sponges efficiently hold water and slowly release it as the plant’s roots require, ensuring a consistent moisture supply.
The Environmental Cost: Why Peat Moss is Unsustainable
The sustainability of peat moss is a complex issue that stems from its harvesting process. Peat moss forms extremely slowly in cool, wetland ecosystems as sphagnum moss decays. These peat bogs are recognized as significant “carbon sinks” because they store vast quantities of carbon—considerably more than forests. The act of harvesting peat moss releases stored carbon dioxide, a major greenhouse gas that contributes significantly to climate change. While some scientists suggest that peat bogs could play a role in mitigating climate change, the increasing temperatures and droughts caused by climate change itself pose a threat to these vital ecosystems.
The peat moss industry asserts that it harvests less than 2% of the total existing peat supply annually, suggesting that this extraction rate is sustainable relative to the demand. However, despite this seemingly small percentage, peat bogs cannot regenerate quickly enough to consider peat moss a renewable resource.
Paul Short, president of the Canadian Sphagnum Peat Moss Association, acknowledges the slow regrowth of peat biomass, stating, “We cannot replace the peat biomass that we remove from a bog in a human being’s lifetime.” He also notes that the CSPMA is involved in substantial restoration efforts, including reintroducing sphagnum moss to harvested areas to restart the natural peat formation process.
Despite these restoration attempts, it is estimated that harvested peat bogs require thousands of years to recover fully, particularly to reach the same levels of peat quantity. Chalker-Scott emphasizes, “It’s almost impossible to get it back to the way it was. I compare it to cutting down old-growth forests. Sure, you can plant new trees, but it will take a long time.”
Linda Chalker-Scott Quote
It’s almost impossible to get it back to the way it was. I compare it to cutting down old-growth forests. Sure, you can plant new trees, but it’s going to take a long time.
— Linda Chalker-Scott
Peat bogs are recognized as the largest terrestrial carbon sink on Earth, playing a crucial role in reducing the greenhouse effect caused by excessive atmospheric carbon dioxide levels. When peat moss is extracted, it not only releases stored carbon dioxide but also diminishes the planet’s capacity to store future carbon emissions.
:max_bytes(150000):strip_icc()/Peat-Moss-1-95352be9766f4b57bc894012faace1ed.jpg)
A gardener uses a trowel to add peat moss-based potting mix to a container, illustrating the hands-on application of this popular gardening material.
Sustainable Swaps: Eco-Friendly Alternatives to Peat Moss
Chalker-Scott strongly advises against using peat moss altogether. “It doesn’t do anything that’s crucial for plant life,” she argues, suggesting its benefits are not irreplaceable. “Otherwise, there wouldn’t be any plants except right around peat bogs.” While peat moss enhances soil water retention, it is not essential for successful gardening. Given the slow natural regeneration of peat moss, its harvesting is inherently challenging to make truly sustainable. If it’s not a necessity, many gardeners and environmentalists question why we should use it at all.
Fortunately, there are numerous viable alternatives to peat moss. When purchasing bagged potting mixes, consumers can look for peat-free options by checking product labels. These mixes often incorporate plant-based substitutes like coconut coir (a fiber derived from coconut husks), recycled paper fibers, and compost. Gardeners can also create their own potting mixes using these sustainable alternatives.
While these substitutes may not perfectly replicate the unique properties of peat moss, they are effective. Peat moss creates a very forgiving soil environment, allowing gardeners some leeway with watering – plants can often recover from both underwatering and overwatering in peat moss-amended soils. With alternative materials, more careful attention to watering may be needed. “I think for gardeners, there’s going to have to be a little experimentation to see what works best for them,” Chalker-Scott advises, encouraging a trial-and-error approach to find the best peat moss alternatives.
For those who have difficulty finding completely peat-free mixes, looking for the CSPMA logo on bagged products can be a compromise. This logo indicates that the peat moss used comes from bogs where restoration efforts are in place. Although full peat regrowth is a lengthy process, these initiatives aim to help harvested bogs return to functioning ecosystems, even if they differ from their original state.
Ultimately, as gardeners, increasing our awareness of the origins of our gardening materials empowers us to make informed and responsible choices about what we use and how much we consume. While there is no single perfect solution to eliminate peat moss use, embracing sustainable alternatives allows us to provide our potted plants with the necessary growing conditions while minimizing environmental impact.
