On the QT | The Official Newsletter of GWA February-March 2016 | Page 16
SUSTAINABILITY
ANNE MARIE VAN NEST
What’s next in organic
waste management.
Is mandatory residential composting coming to your town?
Plastic composting bin,
Fort Mason Community Garden,
San Francisco, California.
As cities and municipalities try to control
waste removal costs, increase pay-per-throw
services and provide alternatives to landfills,
composting is attracting greater attention.
We’re seeing school lunchroom composting
programs in San Francisco, bans on Seattle
food waste in the trash and mandatory composting in Lafayette, Colorado.
Concerns about mounting food waste are driving
this quest for new composting applications.
Jennifer Brooks writes in The Blue Review that,
in 2012, Americans tossed 20 percent more food
into the trash than they did in 2000 and 50
percent more than they did in 1990. Roberto
A. Ferdman in The Washington Post reports that
Americans throw out more food than plastic,
paper, metal and glass. He cites a National
Resources Defense Council estimate that “as
much as 40 percent of America’s food supply
ends up in a dumpster.”
Setting aside the larger issue of reducing food
waste and improving the management of our
food supply, how can garden writers help our
audiences manage their organic wastes better?
One easy way is to educate non-gardeners about
different composting options, guiding them to
the method that is right for them and helping
them avoid problems that may cause frustration.
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CHALLENGES
Household composting commonly uses small
plastic bins with lids and side ventilation – the
must-have items for back yard composting
during the 1980s and 1990s. The idea of throwing
organic refuse in the top and having black gold
come out the bottom after just a few months
was a romantic notion soon shattered by reality.
Compost must be turned to mix the materials,
distribute moisture and incorporate oxygen, but
these small bins just don’t have enough room for
that without taking the bins apart. Even unturned,
organic material will decompose eventually – but
how long are most people willing to wait?
If homeowners are not informed about the need
to provide a good balance of materials (carbon
and nitrogen, ideally in a 30:1 ratio), they may
fill the bin mostly with leaves or grass clippings,
causing the pile to decompose very slowly, or
the grass clippings to become a steamy, smelly
mound of green slime.
To overcome some of these challenges, garden
writers can highlight larger compost bins that offer a greater chance of success, or offer advice on
creating bigger bins made from recycled materials such as pallets, chain link fence, snow fence,
hardware cloth or concrete blocks. Three-bin
models allow for turning one stage of compost
into a neighboring bin for further decomposition.