The Garden Curator

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The Uncultivated Plot

Just as processed food took the world by storm last century, the tendency to process the earth also became common practice for gardeners.  We were taught to dig and churn the soil every time to prepare for planting. There was an element of conquest to gardening that has thankfully softened in more recent times.

In probably 80% of the gardens here I've chosen a no-dig approach.  Our soils are good basalt soils, though reasonably shallow in most parts of the hill-top garden, so cultivation would be detrimental to fragile soil structure which is so important to garden health.  If I'm honest, another reason is the reduction of back breaking and unnecessary digging, and I wanted to avoid the use of mechanical cultivators which would have churned subsoil into our precious topsoil.  Cultivation also brings weed seed to light, so I find I can keep weeds from germinating by reducing soil disturbance.

The no-dig garden, layered with cardboard, newspaper and thick lucerne hay and planted with propagated tubestock.

While many no-dig methods involve multiple layers of materials - paper, compost, hay, manure, more compost - my methods are much simpler and are strictly speaking not entirely "no-dig".  I follow these steps:

  • Mark out the garden area and cut a shallow trench edge.

  • Mow the area very short to catch any grass/weed seed.

  • If the weeds/grass in the area are annuals I leave them or spray with an organic herbicide like Slasher. The paper/cardboard will also starve them of light and they'll die. If there are tough and invasive running grasses like couch or noxious weeds, I do choose to use a stronger herbicide, just once. When done the first time then layered heavily with paper and mulch, I rarely have to reapply and avoid it at all costs! Some no-dig gardeners cover the area with thick black builders plastic for a period to "cook" the weeds, though I don't feel comfortable using it.  It smells strongly of petrochemical so I wonder if it's worse than the herbicide.  An issue for debate!

  • Sprinkle the soil with blood and bone or well rotted manure. 

  • Layer over thick newspaper and/or cardboard, making sure to overlap the sheets and remove any plastic packaging materials on the cardboard.

  • Over the top of that layer thick "biscuits" of lucerne hay, ensuring that these too are overlapping.  I make sure the biscuits (the name given to the slices of hay that peel off a bale) are 10 or even 15cm thick, much thicker than the usual top-up mulching of 5cm or less. 

  • It is beneficial to leave the bed for a few weeks or more before planting to allow everything to settle, and the worms to get to work.  You'll see then when you lift the layers that the worms are having a party underneath, munching on the hay and doing all the soil improvement work for you.

  • When time comes to plant, carefully tease a hole in the hay, cut a small slice into the paper/cardboard beneath, and cultivate a planting hole suited to your pot size.  Fold the paper and mulch back around the base of the plant keeping it clear of the stem.

  • I find this thick layer of mulch keeps the soil damp for months and doesn't need topping up for a year, even two if the season has been dry.  When that time comes I just add a thinner layer of hay over the top.

The same garden, just five months after planting.

A few of important points to note:

It's vital that the soil is fully moist before adding the layers above.  Dry soil will simply stay dry beneath due to the thick layers above.  Moisture will be retained under the layers for months, and as the materials break down additional moisture will penetrate.

Lucerne hay is my preferred mulch by far.  The lucerne plant is a legume, so it will add nitrogen to the soil, enriching it with nutrients and organic matter as it breaks down. Importantly, the hay must be free of weed seed so do check before purchase.  The small wrapped packs available from garden centres are fine though the most expensive way to buy.  Bales can be sourced from livestock produce stores or in some cases direct from growers. Second or third cut lucerne is the preference, first cut is best avoided as it can carry weed seed.  First cut is the first harvest for the season and often contains weed seeds.  Second cut will be a cleaner hay with lots of leaf matter, while third cut is clean and more woody.  

In our garden we have begun with "virgin" undisturbed soils.  If you are gardening in an area where soils are already compromised or even non-existent, a levelled housing estate for example where soils have been stripped, conditions may be very different. In this case it's important to seek site specific advice.

 The results here speak for themselves.  The gardens cultivated first were much slower to establish, while the no-dig beds have sprung to life, content and healthy.