Heatwaves that shimmer reality towards nightmares, water shortages and power cuts likewise turn life — and gardening — into a massive endurance test that is increasingly difficult to tolerate.
In such dire circumstances, anything that makes life easier is to be welcomed with open arms, therefore, whilst there is no immediate solution to the rapidly-increasing climate change and associated problems this brings or to a paucity of water, the fact that there is a water and labour-saving method of gardening, is wonderful news indeed.
No, this is not a sales blurb for fancy, ultra-expensive, computerised or other gadget assisted irrigation techniques but a realistic, much-needed, step backwards in time to a lesson which should have been well-learnt from history.
A newer term for an old method of gardening that should have been learnt from history
It has new names now, names intended to make it sound like a brand new, therefore ‘modern’, discovery but the truth is that ‘Sunken garden beds’, ‘Lasagna gardening’, call it what you will or what the latest crop of gardening gurus decide, it came into being hundreds and hundreds of years ago, possibly in ancient Syria first, before being popularised by the Moghuls.
Quite simply, this incredibly simple, ultra sensible, water-saving gardening method which should never have fallen out of fashion let alone by the wayside, consists of cultivating vegetables, flowers, herbs, even shrubs and trees in self-shaded, water-retentive, below actual soil level, meticulously created beds which, by the by, feed themselves, organically, too.
Making such a bed isn’t at all difficult and costs very little — if anything at all.
It is best to make a series of reasonably-sized beds rather than one large, unmanageable one: anything from approximately two meters x one meter up to four meters x two meters being ideal.
After marking out the perimeter of the bed, remove the top three inches of ‘top soil’, weeding as you go, and set aside. Excavate a further 12 inches or so of what is called ‘sub-soil’ — this contains very little plant nutrition — and use this sub-soil to raise the ground level, equally, all around the excavated hole, to the width of an acceptable footpath, firmly tamping it down as you go so that it remains in place then, when this is done to your satisfaction, cover it with lengths of strong cardboard — recycled cardboard boxes are perfect for this — to form a weed proof, raised footpath around the under-construction bed.
Next: Spread a layer of wet newspapers in the base of the hole, laying them up to an inch or so thick. On top of the newspaper layer, spread a one- to two-inch deep layer of old, well-rotted, preferably organic animal/chicken manure, and give it a good watering to settle it into place. Then add the next layer of ‘lasagna’ using, this time, something nitrogen rich and green such as lawn clippings, weeds (as long as they have no seeds attached), fruit/vegetable peels, coffee grounds/tea leaves, etc. Water it down once more and continue doing so between each brown (carbon) and green (nitrogen) layer until the ‘lasagna’ is almost level with the original surrounding ground area.
The ‘lasagna topping’ is then kept aside, original top soil mixed 50/50 with either well-rotted manure or organic compost or 50 percent top soil, 25 percent manure and 25 percent compost. Top off the ‘lasagna’ with this, mounding it up if necessary and then watering it down.
Leave, undisturbed, for a week or so then water it, leave for a second week when, all going well, you will clearly see that the ‘lasagna’ is sinking down. Water it again, allow it a third week, by which time, as the ingredients are decomposing, it should have sunk some more which is when you can get to grips with planting it. If putting in plants/plug plants/shrubs or trees, plant them in the normal way, digging down through the ‘lasagna’ layers and thoroughly water in as per usual and continue irrigating regularly until the transplants are settled into place.
This is when the natural composition of the sunken bed will take over. Not only will this sunken bed retain moisture, it will also generate moisture as the layers rot down (these layers releasing all the necessary plant nutrients as they do so), plus, it will automatically attract soil moisture from the immediate surrounding into itself too, thus incredibly reducing the need for actual irrigation. If sowing seeds, these are sown as per usual and watered as per usual until the resultant plants are well-established, at which juncture, the gardener needs to keep a vigilant eye on soil moisture, only watering when absolutely essential.
The initial hard labour of excavating, assembling and arranging ingredients, is well worth the effort, as is the seasonal topping up of additional layers in between crops.
Green ingredients include: grass clippings, green leaves, organic manure, organic compost, vegetable/fruit waste — if you don’t have enough of this there is often lots dumped next to fruit markets and bazaars — coffee grounds/ tea leaves, any green plant material as long as it is free from pests and diseases.
Brown ingredients include: newspapers, cardboard — if used in the actual ‘lasagna’ it is best to tear up or shred if possible — straw, sawdust, dry leaves, twigs, coconut waste.
The ingredients, both green and brown, are those that would normally be used in composting and, in a different kind of way, this is exactly what you are doing but in a pit not in a bin or heap.
- The width of the beds should be kept not more than two-arm lengths, as this enables planting/weeding to be done without the gardener having to stand on the actual soil: standing on soil compacts it and is bad news for general soil health.
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Published in Dawn, EOS, June 24th, 2018