Living Soil is a growing method centered on the microbial life inside the soil. Through evolution over thousands of years, Mother Nature has developed a symbiotic relationship between the plants and the microbial life in the soil: fungi, bacteria, protozoa, and many other types. These microorganisms form a soil food web that help feed the plants, in exchange from carbons and sugars that the plant releases (extrudes) through their roots into the soil. In this organic style of growing, the power is given back to the plants, who as living beings have evolved over time to learn to feed their own needs by finding what they require in the soil in which they live. It is this ecosystem in the soil and its relationship with the plant that we call living soil.
The mix was originally intended not for species specificity but what’s easiest and cheapest but “good enough”. I had done a lot of research on “living soils”, had a career in a related industry so knew of “structural soils” and figured why not give it a go on the smaller scale.
I grew several species in the trials, the trial pots were 70L and at the moment have Eggplants in them, some had chillis, and they have had multiple generations. Cannabis is illegal to grow here but the Eggplant ones had a previous species in the same pots that grew over 3m high and were males. They were cut off later and thr stumps remained in pots like normal living soil.
If you glance at the article, and use “structural soils” as a search term elsewhere, again there are lots of different recipes from trees, to gardens, to nurseries etc. I’ve told other gardeners how good it is for what it is and you can see them glaze over, I don’t know of anyone who even gave it a trial after I explained my results. But then biochar isn’t a common thing either.
So with that in mind, I keep sharing just those last 4 pics not to help people but just plant a “seed” of an idea. Bark-based soils are terrible, most people don’t get that and most landscaping bulk soils are built for cost efficiency not structure. Gravel, with some prior planning, could do a bulk amount of beds if one needed it with decent results. The same nutrient adding horticultural rules apply. Shifting to finer gravel as per article allows safer manipulation of top layer if one was growing annuals, one of my other trials switched to a finer stone and was better for that (different from what’s pictured).
With these trials I ran alongside a 1/3rd mix of a traditional living soil, 1/3rd moisture/air/nutrient with the same additives and the gravel pots grew just as well as it.
Wow, thanks for writing all that up and introducing me to a whole new concept!
I’m going to have to read a bunch more and experiment with that sometime.
That’s OK. I was on reddit (and came here for discussion) so that’s what I do.
What I didn’t mention is the weight. That’s the negative. But if you can put it into 100L+ more permanent positions, it’s OK for that.
Common corrugated steel beds in a raised bed layout are probably where it would shine as you could work out your volume and just order that exact amount at once. Compost and biochar you can do separately at the 7.5% rate.
Edit: I’ll add in previously linked article for other readers:
https://www.biochar-journal.org/en/ct/77-Planting-Urban-Trees-with-Biochar
And here is the UK site:
https://stockholmtreepits.co.uk/ - https://www.researchgate.net/publication/341343983_Tree_Pits_with_Structural_Soils_-_Practice_Note_Version_12
https://medium.com/carboculture/how-to-use-biochar-for-structured-soil-plant-beds-in-urban-areas-8a45108e799