It is a spring ritual in Saskatchewan to haul out the rototiller and “work” the garden soil in preparation for spring planting. The conventional thinking is that tilling loosens the soil, breaks up clumps and hardpan, lets air into the soil, kills the weeds, and makes planting easier.
The reality is that tilling, whether by machine or by spade, doesn’t do any of these things very well, if at all. Mostly, it is counter-productive to the longer-term health of your garden. It loosens the soil to the point of pulverizing the soil aggregates – those fertile cake crumbs that are the foundation of healthy soil structure and plant nutrition. Tilling destroys beneficial microbial life, reduces water holding capacity, and sends valuable carbon floating into the atmosphere as CO2. The loss of aggregates leads to soil compaction. Tilling brings weed seeds to the surface for germination. It mangles the earthworms that build humus and aerate the soil.
So, what’s a gardener to do? How do I loosen up the soil and get those seeds into the ground? Here are some ideas:
- Practice minimum or scratch-tilling in the vegetable garden, where only the surface is broken to mix compost or organic fertilizer with topsoil;
- A good scratch tool is the garden fork;
- To aerate the soil, drive the fork deep and wiggle it. Don’t turn the soil. Some use a broadfork for this, but a garden fork works also;
- Hand pull weeds;
- Never till the perennial or shrub beds, or around trees. Use mulch, and practice chop-and-drop;
- Never allow bare soil – use mulch and groundcovers;
- Feed the microbes and insects in the soil with mulch, compost, and organic fertilizers. The microbes and insects will till the garden for you, and do it much better than you can. They create plant nutrients at the same time that they are improving soil structure.
In a future posting, I’ll talk about how to build new garden beds, whether using existing or new soil.