No-till soil preparation method for vegie garden

No-till soil prep is a way of growing crops from year to year without disturbing the soil through tillage - meaning you improve soil health over time rather than consistently degrading it.

It's a method quite common in the market-gardening community and something we're starting to use at our own place now that we have nice, straight-ish beds.

We used the no-till method to help us prepare the soil for a small garlic patch in an area we had been growing green manures.

This method uses silage tarps as a form of weed and crop control, meaning instead of digging in your green manures (or crops) you temporarily cover the bed in non-toxic, UV-stabilised plastic to do the job for you. I know - it sounds whack and it actually took me a while to get my head around it, but after seeing it in action and seeing how well it worked, I was sold.

The process:

Firstly we cut the green manure crops down to the ground. As they were already pretty short we left all the green waste on the bed.

If your crops are really tall you'll want to remove some of them because too much fresh, green matter can create an anaerobic environment which isn't great for soil life and health.

Pictures: Hannah Moloney

Pictures: Hannah Moloney

We then planted directly into the bed with no digging except to make a small hole for each garlic. We also sprinkled a small amount of gypsum as our soil needs this. This is where you might want to spread a layer of compost, it just depends on your soils and crops.

Once fully planted, water in the crop (if needed) and cover with your silage tarp. We actually used non-toxic black builders plastic as this is what we had available.

While we're a bit unclear whether this is acceptable for organically certified farms we do know some market gardeners who use it in this way who grow chemically-free and grow well. We're comfortable using it as our research tells us this particular type is non-toxic and UV-stabilised.

What's the plastic actually doing? It's suppressing weed seeds and killing any fresh growth currently there (the green manures), but keeping the roots in tact for the soil life to thrive in and around.

It's also drawing up soil life, like earthworms, to the top layers of the soil where it's still dark and moist; all while also heating the soil up, which increases the rate of germination.

The length of time the plastic should stay on the garden beds varies depending on the season, weather and crop rotation system you have in place. We left ours on the garlic for around one month, checking it every now and then to see if it had germinated. Once you can see fairly even germination it's time for the plastic to come off.

The main thing we like about this method, is the lack of competing plants that the garlic has to deal with (garlic hates competitors) and the fact we didn't have to do the usual manual weeding to get it to this point. All we need to do now is water if required and do some light manual-weeding here and there, and that's it until harvesting time later in the year.

  • Hannah Moloney and Anton Vikstrom are the founders of landscape design and education enterprise, Good Life Permaculture.