7/28/2019 Using Mulches
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Using
Mulches
A students guide to
using mulches forclearing ground andweed control
Ornamental bark
Ornamental bark is composted conifer bark. Itis more expensive
than woodchips but moreattractive.
Pros: Excellent for decorative beds.It conditions the soil.
Biodegradable. Goodway of recycling waste material.Cons: Although
it will stop some perennialweeds growing soil must be clear of all
weedsbefore it is put down.
Shredded prunings
Woody prunings and other woody materialproduced in the school
grounds can bechipped or shredded to use as a mulch.Heap them in a
pile to compost for a fewmonths before using on planted areas.
Com-posting will darken the colour of the mulch,giving it a more
natural appearance. Add ni-trogenin the form of grass mowings,
net-tle liquid or nitrogen-rich manures to speedup composting.Pros:
Can be used fresh for paths.Biodegradable. Good use of waste
materi-als.Cons: Home made mulches, may degrade
more quickly.
Straw/hay
Straw and hay will make a good mulch forone season. For the most
effective weedcontrol put straw over a membrane such asnewspaper.
It is better to use semi-rotted
straw/hay.
Pros: Hay contains potash and nitrogen.Straw also supplies some
potash. This mulchis good for fruit bushes. Biodegradable. Gooduse
of wastematerial.
Cons: Hay can containsome weed seeds.
Sawdust
Best used as a mulch inwild areas or to covertree mats. Do not
use sawdust from treated
wood.Pros: Biodegradable. Good use of waste ma-terial.Cons:
Sawdust takes nitrogen from the soiland so should not be dug
in.
Tree mats
It is important to keep 1m area at the base of atree free of
other plants and weeds for three tofive years after planting. If
the area isnt clear,the tree has competition for water and
nutri-ents. Tree mats are made of wool, geotextile orblack plastic.
It is also possible to make yourown using newspaper (see newspaper
sec-
tion). Fasten the mats down by burying theedges or pegging
down.Pros: Wool mats and geotextiles are air andwaterpermeable.
Tree mats can also be usedaround large shrubs.Cons: Wool mats can
be destroyed by birdsusing them for nesting material. Black
plasticis not air and water permeable. Synthetic
(man made) membranes are a non-renewableresource.
DUCHY ORIGINALS HDRAOrganic Gardens forSchools
