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Class Level and Curriculum Links
Primary Schools: Senior Classes in primary schools.
SESE Science:
Strand: Environmental Awareness and Care
Strand Unit: Caring for the Environment
* Participate in activities that contribute to the enhancement of the environment
SESE Geography:
Strand: Environmental Awareness and Care
Strand Unit: Caring for the Environement
* Idenitify and discuss a local, national or global environmental
issue
Junior Certificate Geography
Investigating the growing properties of peat and peat substitutes
Peat is a well known gardening material but its use is causing concern. The bogs where it forms are found in only a few parts of western Europe. These are being dug out at an alarming rate which, if continued, will destroy many bogs within the next 10 years. If this happens, habitats, as significant to Europe as the rainforests are to the tropics, will simply disappear.
In this exercise you can find out about some of the properties of peat which gardeners find useful. These can be compared with garden products that do not contain peat. Other investrigations include making compost and finding out how much peat in used in the school and home gardens.
Investigating peat
(NB: use raw peat with no added fertilizers. Don't buy peat for
this, use an old bag that some one else already has).
1. To test the water holding properties of peat: Saturate
a sample of raw peat with water. Weigh the peat when wet and
when dried out.
2. To test the acidity of peat: Use raw peat-add distilled water-measure
acidity with indicator paper, liquid or pH meter.
3. To find the humus content of peat: Use dried raw peat-burn
the peat and weigh the remaining non-organic material. The proportion
of the peat that is organic matter (humus) can be worked out.
Do each test more than once to obtain typical results for
peat.
Carry out the tests with peat substitutes, for example: coir
(from coconuts), composted bark and leaf mould.
How close to the properties of peat do the substitutes come?
Growing bog plants
Use peat alternatives to grow bog plants such as heather's. The
best ones to choose for this purpose are composted bracken or
pine needles. Keep moist with rain water to avoid lime. Outdoors,
bog plants can be grown next to (or instead of) a pond. Many
gardening books and garden centers can supply further details.
Testing the growing properties of peat and substitutes
Use raw peat, peat based compost and the substitute based composts
you are testing. Also try ordinary soil, sand, sawdust or other
materials.
1. Sow seeds such as sunflower, soaked peas or nasturtium,
in each sample.
2. Give each sample the same amounts of water, light and warmth.
3. Observe and measure how well the plants grow in each material.
How do the substitutes compare with peat for growing plants?
Making Compost
Compost forms when dead plants are encouraged to decay with enough
air to support bacteria and fungi but not enough to allow complete
decomposition. Use lawn mowings, waste vegetable matter or any
soft green growth and brown materials such as autumn leaves,
newspaper, twigs and woody stems.
1. Make individual stacks as large as possible of each material
in the school garden.
2. Make stacks of mixed materials making sure to include green
and brown materials.
3. Leave some stacks undisturbed, mix up the contents of others
weekly.
4. Keep some stacks dry, others moist.
5. Take the temperature of each stack every day.
Which stacks produce the most heat?
Are they the stacks that produce compost most quickly?
Are they the stacks that produce the best compost?
Test your compost as a peat substitute.
How well does it perform?
Conducting a peat use audit
(finding how much peat is used at home and at school)
1. Are house plants at home or at school grown in peat based
composts?
2. Which substitute based composts are used, if any?
3. Do the substitutes work as well as peat?
4. What is peat used for in your garden or the school grounds?
5. Which peat substitutes are used, and what for?
6. Do the substitutes work as well as peat?
Is it right to use peat when substitutes are available?
How important is it to conserve peat bogs for wildlife and our
heritage?
