Sure enough, like washing your car or forgetting your umbrella, hand watering the garden plantings the other day was all it took to prompt a series of early-summer rain squalls to pour much, and much-needed, water upon the backyard and my pile.
This evening after work I tip-toe across the sodden lawn to check in on my pile. Mowing will have to wait until the grass dries out, and with backyard cookouts postponed, the kitchen bucket has been slow to fill with its summertime surplus of watermelon rinds and silky corn husks.
My pile looks like an upturned bowl of brown mush. Though the recent rain has likely soaked down only a few inches through the sodden outer layer, I know that much of what lies underneath is saturated with moisture from another source: Grass clippings. I read in Compost Fundamentals, that grass clippings are more than 80 percent water, and, more worrisome, that a compost heap that is more than 70 percent water can quickly devolve into a stinking, anaerobic mess.
My pile is drowning in grass.
“Aeration is necessary in high temperature aerobic composting for rapid odor-free decomposition,” I further read in Compost Fundamentals, a website managed by the Washington State University Extension. “Aeration is also useful in reducing high initial moisture content in composting materials, which reduces the pore space available for air as well as reducing the structural strength of the material. This permits greater compaction and less interstitial or void space for air in the pile.
“If foul odors of anaerobic and putrefactive conditions exist when the pile is disturbed either by turning or by digging into it for inspection purposes, turn the pile daily until odors disappear. No matter how anaerobic a pile may become, it will recover under a schedule of daily turning that reduces moisture and provides aeration.”
I’ve tossed and tumbled the influx of fresh clippings with clutches of old and dry leaves, but even so, the clippings tend to compact into a suffocating layer, prompting a riot of hothouse bacterial growth that sucks up all the available oxygen.
Tonight my pile needs bailing out. I consider plunging into it with the pitchfork, but that project is too ambitious for the time I have on hand. I decide on a more surgical approach, and have just the tool for it: A seven-foot length of metal rebar I use to give my pile needed gulps of air, more like an emergency tracheotomy than a full-scale resuscitation.
“Some prefer to manage a hot or thermophilic pile for several weeks, then stop turning the pile letting mesophilic organisms take over, which encourages fungi and actinomycetes development. Fungi and actinomycetes are the best decomposers of woody matter, such as sawdust or branches. Actinomycetes gives compost the earthy smell—like that of the forest floor.”
That’s pretty much my goal for tending a backyard compost heap — to have it exist as a fragment, a fragrance, even, of the natural process of decomposition, only speeded up by human hand.
So I grab the rod of iron rebar from its resting place against the back fence and gingerly make my way up atop the log containment walls to give my pile a good poke deep inside.
The length of rebar is my divining rod. Like hand-watering, aerating my pile with the ribbed metal rod gives me a kind of kinetic, x-ray insight. With each successive thrust through the top layering of matted leaves, I not only create passageways for fresh air, but also get fresh feedback about what’s going on inside and out of sight. It’s another tactile, probative, way of staying in touch with my pile.
“To compost well, you must ‘think like a microbe’ and create the best environment to support microbial activity,” I learn from Florida’s Online Composting Center, managed by the University of Florida. “Microbes have similar environmental needs as people: water, air, comfortable temperatures, and food. Because they reproduce so quickly under ideal conditions, microbes may deplete the available oxygen through their activity. Therefore, it is important to aerate your compost.
“You can aerate your compost by turning it. This directly incorporates oxygen into the pile. You can aerate by adding bulky items. Bulky items provide air channels so that oxygen can flow into and through the compost. Bulky items also keep the pile from settling and compacting, which could restrict oxygen flow. Bulky items include oak leaves, pine needles, chipped twigs, and straw. You can aerate by probing the pile with a piece of rebar or an aeration tool. Simply probe the devise in several places in the pile. This will create passageways for air to enter the pile.”
Though I’ve dug out both front and back walls of rotting leaf mold to add cavalcades of fresh green manure to its sloping sides and on top, the epicenter remains out of reach with the pitchfork. Probing my pile with the rebar is like sticking a knife into a loaf of bread baking in the oven. I can tell that my pile is well on the way of becoming a uniform heap of ripening compost, though the rod meets more resistance is it pokes through to the untouched core, the undiscovered country.
The tip of the rod emerges from the mix steaming hot, and surely these thrusts give it much needed air. My probing takes only a minute, the exertion balanced by the trickier task of not slipping off the slick tops of the log walls. As much as it needed the recent rain, I know my pile also needs big gulps of air, and after a couple dozen thrusts from above and at ground level, it’s now riddled with slender shafts of space through which to breathe.
One of the blessings of my pile is that it’s as low maintenance as I want it, or need it, to be. It places few demands on my time, asks nothing of me, and accepts only and all of what I care to give it. And best, the thing it needs most is what’s most valuable and free and easy of all to give: Air.