Monday, July 23, 2007
One of the things that I did back in 1999 was to buy and use a worm farm. My main motivation was to use the worm casts in the garden. Also to have less smelly garbage in the bin. If I had calculated whether this reduced or increased green house gases, my thought would be that it was much of a mulchness. Whether my food scraps rotted slowly in my wormfarm and garden, or in a landfill was not much different. In fact I would have thought that in a landfill the carbon would be buried deep underground to become coal in the distant future ie - sequestered. However, recent studies have shown that in a typical landfill and typical worm-farm, the worm farm would absorb the CH4 very well, and the landfill not at all. So it would seem that I was inadvertently helping the environment... Not so fast. As I recall at about the same time, we had a child and to give ourselves more time for gardening, we switched from reusable to disposable nappies exclusively. So instead of nappy-waste going down the drain and into sewage treatment plants to fertilise golf courses etc; it was ending up in the landfill generating methane. Besides which, I never really had enough worms to absorb all foodscraps, so plenty still goes in the bin. And the worm casts in my garden? Myriad tomato, rockmelon, pumpkin and pawpaw seedlings pop up from the casts. I never know whether to try to cultivate them, or to pull them out to leave room for the plants I'm trying to fertilise with the casts.