Issues
Peat Milling
In recent years milling has become the dominant technique
for large-scale peat extraction across Europe. Peat milling
is unsustainable, destroying the biological, archaeological
and landscape value of peatland. It is essential to increase
the use of peat alternatives and decrease the amount of
peat we use in our gardens.
The milling process
Before milling, the bog is extensively drained. This may
take years, as it involves progressively increasing the
depths of the drains to avoid collapse and support the weight
of the milling machines.
When the bog is fully drained all the vegetation is removed
and the ground is levelled. The top 15mm is then milled
to produce a powdered peat that is left to dry. The milled
peat is turned several times using a harrow to assist the
drying process. When the peat is dry enough, it is gathered
into ridges for a large vacuum harvester to collect.
| Peat
milling |
|
Harvester
emptying load |
 |
|
 |
Depending on weather conditions, there may be as many as
12 harvests of peat in a year, removing a depth of up to
200mm of peat. Since it takes approximately 1 year for 1mm
of peat to form, this represents 200 years' worth of peat
removed every year.
| Peatbags |
 |
The horticultural use of peat
Milled peat is used in a variety of industries. For example,
every year the Republic of Ireland uses over 12 million
m3 of milled peat to produce electricity, and
a further 1 million m3 to make peat briquettes.
However, the main use of milled peat is in the horticultural
industry, as a soil improver and growing medium for container
plants.
In 2001, the United Kingdom used 5.4 million m3
of growing media and soil improver:
- 63% of this was peat
- 37% was alternative such as bark, coir and green compost
More than half of the peat the UK uses is imported from
other countries, particularly the Republic of Ireland and
the Baltic states (see Table 1 below).
Table 1. Sources
of peat supplied to all horticultural markets in the United
Kingdom in 2001
|
United Kingdom
|
1,486,000
|
36,000
|
1,522,000
|
45%
|
|
Republic of Ireland
|
1,422,000
|
59,000
|
1,481,000
|
44%
|
|
Baltic States
|
375,000
|
17,100
|
392,100
|
11%
|
We can divide peat users in the horticultural
industry into four groups:
- amateur gardeners
- professional growers
- local authorities
- landscape contractors
Amateur gardeners use approximately two thirds while professional
growers accounting for only around one third of the peat
used. Local authorities and landscape contractors use only
a very small proportion of peat.
Amateur gardeners
Gardening is a very popular leisure activity with all social
groups and ages. Approximately 85% of people in the UK have
access to a garden and in recent years there have been significant
increases in sales of all gardening materials. A large increase
peat consumption between 1993 and 1996, from 1.55 million
m3 to 2.27 million m3, was largely
due to the increased use of growing media for container
and patio gardening.
| Peat alternatives |
 |
Amateur gardeners usually buy peat-based growing media
in ready-to-use bags, and many may be unaware of the adverse
effects of milling on peatland habitats. Encouragingly,
there has been a large growth in the use of peat alternatives
by amateur gardeners in recent years.
However, this has not reduced the amount of peat being
used. The total amount of materials amateur gardeners use
continues to rise, so the increased use of alternatives
has simply allowed the amount of peat used to remain fairly
constant.
Professional growers
Milled peat is important for the professional grower as
it has a proven performance and consistency, good availability
and is competitively priced.
Traditionally the use of peat alternatives with professional
growers has been relatively low due to the quality requirements
and economic implications if products do not meet existing
standards. The main alternatives were once just by-products
from forestry and agriculture, such as bark, wood waste
and cocoa shells. Green compost was unpopular because of
concerns regarding its variability, pathogens and nutrient
levels. Recent research and development has done much to
overcome these problems. In 2001 green compost accounted
for 16% of peat alternatives used in the UK, but this is
likely to increase substantially because of current recycling
policies.
Since 1999 two major factors have contributed to the increased
amount of peat alternatives professional growers use:
- The quality, standard and availability of peat alternatives
has improved greatly.
- Major retailers are insisting that growers supply plants
grown in 'reduced peat' or peat free media.
Retailers are undoubtedly responding to factors such as
increased public concern about conserving peatland habitats,
lobbying from conservation organisations and the Government's
increasing emphasis on the sustainable use of resources.
Further developments in waste management policy may produce
recycled wastes with the potential to substantially reduce
peat use in horticultural markets.
