Peat moss is not a sustainable option for gardening on any level.
No matter how good of a product it may be for anyone, the mining of peat moss is an incredibly destructive industry that is harming not only sensitive habitat but some of our largest carbon stores on the planet. Now, before you think I'm all up on my high horse about this subject, please note that I still use it in some of my gardening projects. It is hard not to. I am writing this post as a cry for help in order to get a conversation going about some sustainable and effective alternatives to this "blood soil."
Peat is the product of the natural processes that bogs go through. Sphagnum moss, the main species of a bog ecosystem, and other plant materials don't decompose in bogs. Instead they build up and compact to form what we know as peat moss. For centuries, this has been harvested and dried as a source of heat and energy for native peoples. Today, because of its moisture holding abilities and rather sterile, acidic nature, it is heavily mined for the horticultural trade. Most of the peat sold comes from Canada. Canadian companies mine their bog habitats for this product. The Canadian peat companies will tell you that it is a renewable resource and that mitigation offsets any damage being done. This is a bold faced lie. Bogs are incredibly sensitive habitats. They are the product of thousands of years of very particular natural processes. They hardly regenerate themselves if at all. Mitigation efforts are also pointless. Bogs that have been "mitigated" do not return to their fully functioning state ecologically.
To make matters worse, the industry loves to claim that there are no alternatives to peat moss out there. This is simply not true. I have researched some interesting sustainable alternatives to peat moss. One product is coconut coir "dust." This product comes from ground up coconut husks. From what I have read, it is also a much more sustainable option. Now, a few things must be said about the efficacy of this material. First off it is naturally high in salt. Most brands must be thoroughly washed before using. I have gotten around this issue by purchasing coconut coir used for amphibian and reptile bedding. It comes in compact bricks and it has the lowest salt levels on the market. Also, it is really low in nutrient value. I do some water gardening so I have a very mature fish tank running and using aquarium water seems to solve this issue for me. Adding coffee grounds can mitigate this as well. I have heard mixed reviews about coir and it is not necessarily the best choice for all types of seeds but it works quite well for me and in the last 4 growing seasons I have finally switched to using coir for germination.
By far my favorite media to use is good compost. Having ready access to a big pile goes a long way. Because compost can be very rich and heavy, I like to mix in wood chips and gravel. This not only weighs my pots down and keeps them from falling over, it increases the amount of roots my plants produce considerably. Every time a root comes into contact with a piece of gravel or wood chip, it branches off hundreds of tiny root hairs, thus increasing the surface area available for water and nutrient absorption. Since I switched over to mixing my own soil using compost, I have noticed my plants are more vigorous and are flowering more often.
Another option I have come across is pine bark. I have not used this but some research papers rank it as good as peat moss in seed germination trials. Has anyone here tried this? If anyone has an opinion on this subject or better yet, first hand experience, PLEASE chime in. If we can't make growing plants a sustainable process then what good are we as a species? Finally, does it make sense to destroy one habitat to foster a handful of species in your back yard?