Dry air, winter frosts, and beneficial insects make organic agriculture in Central Otago a fairly practical management tool; the outstanding problem is coping with under-vine weeds. “Organic” does not always mesh well with sustainable regenerative agriculture, which is what we want. Standard organic management often relies on tilling the soil along the vine rows, cutting through surface roots of the vines and leaving rows of dry soil which blow away in the wind or get washed away when it rains. Our aim is to enrich the soil, not to expose it to leaching and dessication. Regenerative agriculture replaces cultivation with no-till, which in an open field situation may include herbicide, which we want to avoid. Undisturbed soil becomes the home of beneficial soil fungi and bacteria, and a good home for the earthworms which carry organic detritus from the surface down into the soil.
We have for a long time been looking for a machine which can mow under the vines, and now think we have found it, from Italy, a Berti Eco Sprint. This has a long cylindrical rotor with multiple heavy gauge plastic strings which rotate vertically so they slide down the vine trunks without damaging them, and then strip the weeds from around their base. I had worried that this might damage our irrigation drip-lines, but this has not happened.
Using the Berti, we now clear the weeds from under and between the vines, followed by inter-row mowing with our mulching mower which deposits mulch under the vines, where it composts and improves soil structure and fertility.
Is this the ultimate end of the road? No, unfortunately, it still depends on using diesel to drive the tractor. Horses might pull the machines, but can't drive the hydraulics. Electric tractors are still under development, but once we get one our vineyard irrigation and tractor work can all be powered from our large photovoltaic array, and we might become a fully solar-powered vineyard. Still dreaming . .