Alternatives to peat and synthetic fertilizers
Peat has many good properties as a growing substrate. But the use of peat causes large emissions of greenhouse gases and destroys the habitats of numerous plants and animals. Equally problematic is the use of synthetic fertilizers. The Botanical Garden is running a project to test different alternatives to peat and synthetic fertilizers.
What is peat?
Peat consists of incompletely decomposed plant remains that have formed over thousands of years in wetlands.
What is peat used for?
Peat is a good growing substrate for several reasons. It is good at keeping moisture, free from pathogens that can cause disease in the plants, has a good structure that the plants' roots like, is easy to adapt to the needs of different plants, and weighs little. The latter is important in a botanical garden where large quantities of pots and seeds must be handled and moved around.
Why is it problematic to use peat?
The peat in, for example, a bag of purchased "soil" is taken from excavated wetlands. Wetlands store large amounts of carbon, while an excavated peatland releases carbon dioxide. When the water level is lowered, so that the oxygen in the air comes into contact with the peat, it breaks down and carbon dioxide is formed. Even if the cultivated peat comes from wetlands that were dug up a long time ago, the carbon dioxide emission continues both in the peat extraction and in the garden or the pot where we use it as a growing substrate.
What is the Botanical Garden doing?
With support from Lund University’s Sustainability Fund, the Botanical Garden was able during 2024 and 2025 to begin testing various alternatives to peat in the garden and to explore ways to reduce the need for peat. Thanks to continued support, the work will continue in 2026 and expand to include, among other things, trials with fertilisers that can work together with the peat alternatives, as well as the technical systems used for fertigation in the garden.
What can you do?
The aim of the project is to find sustainable alternatives to peat and artificial fertilizers that can be used on a large scale in the Botanical Garden. Equally important is inspiring others to reduce their use of peat, and an essential part of the project is therefore to share information about the Botanical Garden’s work to find alternatives.
You can also make a difference! If you do not want to experiment with your own soil mixes, you can make an impact by asking for peat‑free options where you buy soil. Choose organic liquid plant food and natural fertilizers for your garden and for the plants on your windowsill.