Tuesday, July 28, 2009

Compost Report: A Note from Down Under

I have unbridled enthusiasm for compost. It's totally nutty and weird, but when it comes time to harvest compost I put my hands in the stuff, sniff it, turn it over again and again. My cats look on with suspicious interest. My friends (thankfully a forgiving and understanding bunch) watch with amusement.

For my gardens which cover the better part of two lots, I have two 4X4X4 piles. I harvest about two times per year. I get about two cubic yards of super good stuff per harvest. It's full of worms.

In truth, I'm not a very good composter. I do layer, but should really turn more frequently, water better in the summer, etc. Nonetheless, compost is forgiving: even my slacker style composting pays off in good measure.

One issue I've recognized however is that my starting notions of the scale on which I should compost are no longer suitable for my goals. My original notion was just to compost, e.g. have a compost pile. Super. Did that. Seems to work.

But, now I'm trying stop hauling stuff (soil, manure, etc.) into my garden from without and I'm trying to stop hauling stuff out of my garden (cuttings, sticks, weeds, etc.). Composting is clearly the answer, but I need to improve my technique and probably change the scale of my operations somewhat.

I currently haul out about 3 pickup loads of biomass each year. Most of this is material I currently deem to be non-compostable. That includes invasive species, big woody stuff, and whatnot. I want to eliminate those loads this next year.

Similarly, this year I have hauled in a massive amount of soil, manure, etc. Almost all of that has been associated with a one-time build-out of new garden space over a short period of time. If I'd been in less of a hurry, I could plausibly have built using my own compost, but if my math is correct that would have taken me about 10 years. To put it bluntly, I'm too old for that shit. (Sorry, couldn't resist!) Next year (after my new raised beds are filled), I won't bring anything in.

So, the challenge is really about finding a compost solution for the 3 pickup loads of biomass I produce annually. I think this is a realistic goal. I don't know what the solution will look like exactly, but here are a some starter observations:

  • Sizing a compost pile is a critical part of garden design. It's not trivial, especially if you want more than just 'token' compost. I've learned a lot about the amount and type of biomass my lots produce over the years. I'm doing things to alter those patterns. That learning is telling me the most basic things about how big my compost solution needs to be.
  • Location. Location. Location. Making compost involves lots of schlepping of stuff. Putting a pile in the right place make a huge amount of difference. Locate near gardens, near kitchen, near animals like chickens.
  • Mastication may matter. My lots produce quite a bit of woody stuff. I'm learning to re-use some of that for fuel and for garden supports. The rest has to go somewhere and takes a very long time to compost. Having some means of grinding can accelerate radically. Manual chopping is OK, but time consuming. I'm exploring neighborhood scale solutions, e.g. shared shredder, large long-term piles, etc.
  • Maintenance can speed cycle time quite a bit. My piles go super fast in the summer months. Winter is slow. I could probably get a third harvest in by doing better with maintenance. If so, that's 2 more cubic yards of compost per year...probably a good portion of the pickup loads I'm trying to eliminate.
Stay tuned for solution decisions and notes!

Sustainability: Getting to Basics

Recently I had the pleasure of reviewing architecture student midterm garden design projects. The assignment was geared for sustainability. The projects I looked at revealed a high degree of variety and creativity. Some were quite lovely.

One thing that struck me, however, was how differently the students interpreted what 'sustainability' means. As I realized this, I began to prod a bit by asking questions: "What does sustainability mean?", "What were the sustainability objectives for your design?"

Their good work notwithstanding, the answers given by the students were surprisingly vague and gave opportunity to reflect on how I consider and pursue (or don't!) sustainability in my own garden. The conversations which resulted surfaced a couple of basic things perhaps worth sharing here.

First, sustainability is about balancing inputs and outputs. Better still, it's about zeroing out inputs and outputs within a defined space. If I'm dragging lots of materials into my garden (guilty as charged!), then I'm not balanced. If I'm hauling out lots of materials, I'm not balanced. If I'm consuming more food than I'm producing, I'm not balanced.

I realize this is not a very forgiving definition of sustainability, but it is simple, direct, and measurable. The latter qualities make it a sturdy guidepost for design choices, lifestyle choices, etc. Not to be harsh, but it strikes me that without such a clear and basic way of talking about sustainability, the word and the concept become mostly about style and intentions and not much at all about creating lasting ways of living.

Second, and in a related sense, sustainability always has a specific scope. There's no such thing as generic 'sustainability'. Scope defines the specific realm within which inputs and outputs are zeroed out. It can be thought of both in terms of what things it covers (e.g. soil, water, food, tools, etc.) and in terms of the geography (garden plot, neighborhood, city, region, etc.) which bounds it.

So, I could aim for soil sustainability by reprocessing garden waste to create all of my own amendments such as compost, manure, and the like. I could go for water sustainability by capturing and storing all the water I require. I could go for food sustainability by growing all I eat. But I could also scope my sustainability efforts around soil, water, and food to extend throughout my neighborhood (by trading with neighbors), my city, my region, etc.

In a very practical, daily sense, being able to spell out my sustainability objectives in terms of what they cover and over what geography they apply is helpful to me in identifying specific courses of action that make more sense than others. There are lots of things I could do. Knowing this year, for example, that I want to stop removing large quantities of biomass and bringing in similar quantities of soil amendments gives me something specific to work on around compost, mulching, etc. Next year it could be about seed and start sustainability. Recognizing the geography within which I intend to zero out tells me who I need to help and get help from.

I live a long way from sustainability. Recognizing that makes it clear that getting to sustainability is not just about lifestyle. There's really no daily solution that'll get me there. Rather, a lot of my 'infrastructure' is just plain wrong. That means re-design. Which brings me back to the wonderful and creative design students I had the pleasure to meet recently. They enjoy super opportunities to shape spaces in ways which can actually enable or enhance the likelihood that people will live in sustainable and durable ways....or not. Clarity about what that actually means is a good starting point.