Lake Minchumina — Although I enjoy the substantial job of tilling our large garden, recently I’ve been reading about the benefits of no-till gardening, and I’m almost always in favor of it. Yet I have always tilled, am tilling this year, and tilling shall continue to be one of my Brobdingnagian chores every spring for the foreseeable future.
I don’t contemplate this lightly; gardening consumes much of my life, from garden sets in April through November pumpkin-processing, and provides the majority of our vegetables for the full year.
It’s a conundrum. I totally grasp the adverse implications of turning and roughly disturbing soil. This brutal approach to gardening disrupts microbial life, especially fungal strands, that lends the soil vitality and thus heath to my vegetables that in turn give sustenance and heath to me.
These are the organisms responsible for breaking down organic matter to release the nutrients required by plants to thrive, even helping them absorb those nutrients in exchange for some of that good stuff only photosynthesis can produce. They lend soil substance and help it hold together, retaining both moisture and nutrients.
The common misconception that tilling lightens the soil, allowing roots to penetrate easily, doesn’t hold up. Instead, loosening soil encourages erosion and loss of organic matter and nutrients to wind and water. Tilling is also time-consuming, tedious, repetitive work. So why would anyone do it if they didn’t have to?
I guess that’s the problem. I do have to.
I till mainly for two reasons. One is weed control. Tilling destroys most growing weeds, especially if done during sunny weather. I let plowed-up, exposed weed growth desiccate and die, then rake the tilled ground smooth, exposing any roots that, if left buried, may take hold and re-grow. The loosened soil allows a hoe to penetrate deeply, easily drawing later weed survivors up by the roots to eliminate the rascals instead of watching them spring back to life.
The twirling tines also bury most of the weed seeds lying on the soil surface, often too deeply to germinate. While this may simply put off a weed problem, since seeds underground can survive for years until tilling returns them safely to the surface, it does effectively slow the otherwise rapid seed-weed-seed cycle.
However, the primary reason I till, the one that convinced me that no-tilling was not an option for me, is soil temperature. The ground of Alaska’s Interior remains below freezing for six or seven months of the year, not thawing until two or three weeks prior to planting. During our short growing seasons, soil temperature can make or break germination and growth.
Cold weather crops such as carrots and beets slow their germination at sub-optimal temperatures. Other seeds, planted in cold soil, sit waiting and waiting for soil to warm before even starting to spring forth, while a few warmth-loving crops — beans come to mind — reward premature planting enthusiasm by rotting in place, never coming up at all.
As you know, jump-starting a garden shifts harvest time earlier. In some vegetables, that can make the difference between whether, or how much, of a crop matures. Warming sub-surface soil hurries this along. In addition to speeding germination, the heat increases all that great microbial activity, hastens nutrient uptake, and speeds enzyme activity and metabolism, and hence growth, in plants.
Consequently I till our entire garden — excluding the raised beds — as soon as the soil dries enough after snow-melt. Tilling effectively pulls frigid subsurface soil to the top for warming in the hot May sunshine, while burying the warm surface soil down to heat lower levels.
After a couple days to allow temperatures to stabilize, I’ll till once more, plowing perpendicularly to my initial furrows, to repeat the stirring and heating process. In addition to maximizing soil warmth, this catches any missed ground and breaks up clods, making raking and seeding much easier.
The exceptions, at least in my garden, are the raised beds. Elevated one to two feet above the surrounding ground, their contained soil warms rapidly, and because I’ve added large amounts of compost, weeds pull up easily by their roots. These areas do not require tilling, and if we constructed the entire garden in raised beds, I could give away the tiller.
Unfortunately, with several thousand square feet of garden, the thought of putting it all — even cool-loving potatoes and broccoli — into raised beds is cringe-worthy: ain’t gonna happen. That leaves me cranking up that darn tiller every spring.
Some years ago, I had finished tilling only three-quarters of the garden when the belt broke. I ordered a new one, which took a month to arrive. Consequently I put in the garden without finishing the job.
Well, guess what. Everything grew adequately in the once-tilled soil in spite of a few clods. But the untilled areas saw poor germination, with vegetable growth stunted and delayed and weeds rampant and un-hoe-able.
The upshot: please do not till your garden. Unless you have to.
Trappers and lifelong Bush residents Miki and Julie Collins have written three books. They live in Lake Minchumina.