We are losing soil at a completely unsustainable rate. According to The Soil Association ‘the equivalent of 30 football pitches of fertile soil every minute’ and yet it takes over 500 years to form 1 inch of top soil.
Here in the UK we are fortunate to have deep soils due to our geological and woodland history. This has allowed us to develop and maintain some agricultural and horticultural practices which we now know to be damaging.
Soil is incredible stuff, it’s not just a rooting medium; one tablespoon is said to have more organisms that there are people on the earth. Most of the micro organisms are yet to be identified or understood.
Soil stores heat, holds and filters water, nutrients and gases. It contains mycorrhizae which creates symbiotic relationships between plants and trees. Then there’s fungi, nematodes, insects, earthworms, slugs and snails.
Soil also stores carbon. The more we work with and disturb with soil the more carbon we release and the more we damage the soil structure. We also have to consider the impact of using diggers and reshaping the contours of our patches, there is often a price to pay also in terms of interrupting natural drainage.
Its a tricky thing to come to terms with as a gardener.
We also know that woody plants (shrubs and trees), absorb carbon dioxide as they grow, locking carbon in their cells (this is why we plant trees to offset our carbon footprint). Also plant roots stabilise and protect the soil they inhabit.
Arit Anderson inspired me with the idea of “using gardens as a carbon store’ when she spoke passionately on sustainability and the choices we can make or influence. We can choose to select our planting with this in mind.
Plant things which will do the work for you; weeds aren’t really a problem once the soil is occupied. Ground cover planting can include shrubs as well and low herbaceous plants.
Gardeners can learn from the concepts of agroforestry and forest gardening. Choosing perennial and woody planting as an important strategy to both store carbon, and protect our soils from the disruption of annual sowing and planting.
So protect your soil; only dig when you must, mulch it and cover it.