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"No-till garden, we grow soil!" sign above our vermicomposting bin. |
Why we don’t till
Traditionally, gardeners believed it is beneficial to till soil: breaking up any compacted soil with a hoe or other tools, aerating it, and mixing in organic matter before planting.
However, there is now extensive research showing that tilling actually has an overall negative effect on soil.
In the short term, the soil seems softer, and indeed there can be more oxygen and organic matter incorporated in the soil right after tilling.
In the long run though, tilling actually leads to more compaction, especially in clay soil, and soil becomes more prone to being eroded by sun and water.
On top of this, tilling increases weeds, because it exposes weed seeds to the surface of the soil.
Worst of all, tilling damages the microbes in the soil, which are necessary for plant growth (read more about this in our previous blog post).
Often, these negative effects aren't apparent, because gardeners may be heavily fertilizing and watering to compensate for the poor soil structure and lack of healthy soil microbes.
What we do instead
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| Our curving vegetable beds, mulched with straw, July 2024. |
Top-dressing
We add a layer of compost to the top of the soil. We don’t mix it in; microbes and invertebrates like earthworms do this for us.
Avoiding stepping in the beds
We’ve designed our garden beds with curves, keyholes, and stepping stones where needed, so we can access the plants without having to step in the beds and compact the soil.
Mulching
We add a layer of mulch to our vegetable beds to suppress weeds, retain moisture in the soil, and protect the soil from erosion. In true permaculture fashion, we use whatever organic matter we have on hand:
Adding organic matter
By using organic matter for our mulch (rather than say, a plastic tarp to cover the soil), we provide a food source for the aforementioned microbes and invertebrates. As the mulch is broken down, nutrients are returned to the soil.
Examples include:
- wood chips (acquired for free, from arborists working in the neighbourhood)
- grass clippings
- leaf litter
- straw
- shredded cardboard
- chop and dropped weeds
Perhaps the easiest source of organic matter is chop and dropped weeds, which we’ll go into in our next blog post.
By adding lots of organic matter to the soil without mechanically mixing it in, we create a nice environment for microbes and invertebrates which will create healthy soil and soil structure for us.
Sources:
No-till vegetable gardening for home gardens - Gardening at USask - College of Agriculture and Bioresources. Gardening at USask. https://gardening.usask.ca/articles-and-lists/articles-how-to/no-till-vegetable-gardening-for-home-gardens.php.
Should I put earthworms in my garden? 2020 Dec 11. Extension. University of New Hampshire. https://extension.unh.edu/blog/2020/12/should-i-put-earthworms-my-garden.
Williamson RF, Reay M, Sgouridis F. 2024. Permaculture Management of Arable Soil Increases Soil Microbial Abundance, Nutrients, and Carbon Stocks Compared to Conventional Agriculture. Agronomy. 14(7):1446. doi:https://doi.org/10.3390/agronomy14071446. [accessed 2024 Aug 1]. https://www.mdpi.com/2073-4395/14/7/1446.