Page 19 - Green knowledge 2024

Photo: Morten Günther
Are there good alternatives to peat?
The authorities aim to phase out the use of peat in Norwegian growing media. But are there
good alternatives? The answer, for now, is a cautious yes.
There are substitutes for peat, but so far, replacing
its excellent physical, chemical, and biological prop-
erties has proven challenging. Peat regenerates very
slowly, making sustainable production dependent on
new solutions.
Several producers of growing media have attempted
to introduce peat-free, compost-based blends of
growing media for both private gardens and profes-
sional use. However, according to Haraldsen, none
of these products have reached significant volumes
in the market so far.
“The results from the SUBTECH project show that
several plant species can be cultivated in mixes
where the range of the peat replaced with other alter-
natives was from 25 to 100 %,” says project leader Dr
Anita Sønsteby at NIBIO.
This applies to strawberries grown in plastic tunnels,
as well as certain flowers and herbs. However, not all
crops react the same way. A common factor for all is
that when peat is removed from the growing
medium, fertilization and irrigation must be adjusted
for each plant species.
“The challenge with most types of compost is that
quality, including structure and nutrient content,
varies significantly,” explains Dr Trond Haraldsen at
NIBIO.
Wood fiber, such as Fibergrow® produced by
Hunton, appears to be a promising alternative. It is a
locally sourced, uniform raw material of Norway
spruce fibers. Tests show that wood fiber can replace
peat in blends, and in some cases—such as for
cucumbers and tomatoes—pure wood fiber can yield
better results than rockwool.
The SUBTECH project concluded with a seminar at
Gardermoen in February, where representatives
from research, industry, and the growing media
sector shared their experiences. The follow-up pro-
ject, SUBTECH 2.0, will run until 2027 to further
develop knowledge and ensure stable plant produc-
tion without peat.
Purpose: Collaboration: Funding: Contact: To find viable alternatives to peat in Norwegian growing media.
NORGRO, Gartnerhallen, Hunton Fiber (Fibergrow), ReKlima, Norwegian Agricultural Advisory
Service and Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Belgium
Research funds for agriculture and food industry and Grofondet
Research Professor Trond Haraldsen, Division of Environment and Natural Resources.
Email: trond.haraldsen@nibio.no | Phone: +47 928 04 196
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