YRE Competition 2023
2nd Place - Article
19-25 years old

By Mária Jánošíková

Peat is a popular substrate used for growing acid-loving plants such as blueberries, azaleas, cranberries, and rhododendrons. While gardeners enjoy its benefits, peat is mined from bogs, which are protected and rare habitats. Although many can't do without peat substrates, natural garden enthusiasts know alternatives.

Peat is a common part of garden substrates. It is widely used by gardeners and growers as a natural product that makes soil lighter, plumper and helps to hold water better. However, peat is mined from peatlands, which represent rare and unique ecosystems. New data published by The Guardian showed that more than a third of the compost sold in the UK in 2021 was peat dug from rare carbon-rich habitats (1).

"Peat bogs are a type of wetland, and they are one of the most effective ways of retaining the carbon that is stored in the bodies of plants. That's why bogs are a very interesting ecosystem in the context of climate change," says Andrea Froncová from the Bratislava Regional Conservation Association about the importance of these sites.

ALTERNATIVES EXIST

Alena Paššová Pohorencová, one of the first owners of certified natural gardens in Slovakia, knows the ways in which commonly available substrates with peat, and peat itself can be replaced. In order for a garden to receive this certificate, it must not use artificial fertilizers, pesticides, or peat. Why is using peat prohibited in natural gardens? Because it is a non-renewable resource and its extraction releases a substantial amount of CO2, a greenhouse gas.

According to Paššová, one of the substitutes is the coffee grounds that remain after coffee is made. This is often considered unusable waste. "Coffee is acidic; its pH is around 5. If we add it to the soil or put it under bushes, we will lower the pH to a suitable level for growing acid-loving species", says Paššová. She also recommends revitalizing the soil or compost by adding locust tree bark, sawdust soaked in vinegar water, or pine needles.

GARDENING WITH NATURE

Although there are alternatives to peat, it is best not to grow plants that need it at all: "We avoid ornamental plants, so you won't find heather, rhododendrons or blueberries here. In the garden, we have a few older spruce trees that my grandfather brought from the forest as young seedlings; otherwise, you won't find any acid-loving plants here. In our area, acidic habitats do not occur naturally; therefore, we will not artificially change the quality and composition of the soil," says Paššová Pohorencová.

The gardener further explains: "We do not use chemical sprays; we build variety and diversity, and we also share the harvest with wild animals that live here as they take care of the biological protection of the garden. We had a natural garden long before we knew the criteria for certification. It is my lifelong process to observe the garden and learn how to cultivate it." According to her, one should replace acid-loving blueberries with Saskatoon berries.

PEATLANDS FOR CLIMATE CHANGE MITIGATION

Although peatlands cover only 3-4% of the planet's surface, they store up to a third of the planet's terrestrial carbon, twice as much as is held in the world's forests (2). Therefore, the preservation of peatlands is very important as a mitigation measure in times of climate crisis. The British government is dealing with the legislative protection of bogs. It proposes to end retail sales of peat compost in 2024 and sales to professional growers by 2028 (1).

Peatlands are also found in Slovakia, in the Tatra Mountains, in the Orava region, and along the Slovak-Polish border. There were many more in the past, but they were destroyed, drained, and turned into fields. The remaining ones are considered very rare habitats and have a high degree of protection. As the peat available in shops in Slovakia mostly comes from Belarus, there is also the problem of the carbon footprint created by transporting the substrate to our market.

Peatland conservation and restoration are extremely important, not only as a carbon sink but also to retain water in the landscape and increase the biodiversity of the area. The good news is that within the project "Ecohydrological Restoration of Peat Bogs in the Carpathians", to be implemented from February 2022 to April 2024, twelve rare peat bogs will be restored in Slovakia (3). The project also includes research to find out how much carbon peatlands can sequester and evaluate the effects of restoration to increase this capacity.