It’s true that most plants love peat. It’s light and slightly acidic and it retains water without bogging down soil. But peat bogs, where this wonderful material comes from, are absolutely essential carbon sinks. In fact, while peatlands cover only 3% of the planet, they are the largest of all natural carbon sinks on Earth — they store nearly 500 metric gigatons of carbon. One study I read (linked below) says a single meter deep of peat is approximately 1,000 years of stored carbon! (Honestly, wtf wow.) This means that peatlands store more carbon than all other vegetation types in the world COMBINED and the harvesting of peat releases all that lovely stored carbon into the air; an estimated 5% of CO2 emissions caused by humans comes from the harvesting of peatlands alone! On top of that, peat moss takes many thousands of years to form, making it a HIGHLY NON-renewable resource; once it has been harvested (namely from bogs in Canada and northern America), it is gone for millennia.
There is also the hopefully obvious issue of peatlands being an important ecosystem. While not super biodiverse due to their high acidity, there are many specialty species that can live nowhere else, like pitcher plants and sphagnum moss, and they play a major role in flood prevention. They also provide habitat for some nesting birds and have proved to have a remarkable adaptation to climate change , which is a stroke of good fortune for all of us species depending on the health of the planet. Imagine if climate change was wiping them out, exponentially increasing CO2 in the air? While many of us tout the importance of forests, prairies and wetlands because of the cute or wondrous species that live there, peatlands tend to get ignored, landing them on the shelves of big box garden centers and into our little pots of seeds and gardens we feel oh-so proud about.
The good news is there are plenty of other materials that will act in ways similar to peat moss for planting purposes. A combination of vermiculite, perlite and coconut coir is completely fine for seed starting — seeds need no nutrition at this point in their life cycle, and if you want to pot them on, just add a bit of compost to the mixture. And while it’s true that all these substrates have their own ecological impact, none seem quite as imminently scary as the harvesting of peatlands. I encourage anyone starting seeds to experiment with their own homemade and much cheaper mixes. If you live somewhere with leaf fall, collecting and shredding leaves in Autumn, letting them sit in a pile and rot down over winter, will give you a lovely light substrate that can also be used for starting seeds and mixed into potting soils.
As gardeners and growers, most of us hope to create beautiful and beneficial spaces for ourselves, our friends, and the critters we share these spaces with. But if the means to those spaces does more harm than good, it seems to defeat the purpose in many ways. So give peat-free potting soil a google and a go this season.
DIVE DEEPER
In addition to their immense ecological impact, peat bogs are also where some of the most well preserved remains of early humans–dubbed “bog bodies” — have been found. The Tollund Man, found in Denmark, is arguably the most famous: a 30- to 40-year-old man who died sometime between 405 and 380 BC, shockingly preserved with skin, hair, clothing and fingernails. His face could be that of a man sleeping. Here’s a quickie course on going peat-free offered by Garden Organic. And a nice interview from Gardener Extraordinaire and New York Times Garden Contributor, Margaret Roach with Dr. Brian Jackson, director of the Horticultural Substrate Lab at NC State. University |
