What a curious expression it is to say that a person is ‘down to earth’? We usually use it as a sign of approval; that somebody is plain speaking, without guile or an alternative agenda. They are usually the type of people about whom we might also ‘take at face value’ or ‘call a spade a spade’ or about whom we might say ‘what you see is what you get’. This quality of
openness is one that we lament not finding in our politicians. Yet a frank exterior can often conceal hidden depths.
A surprising number of horticultural or agricultural terms crop up in our lexicon. Perhaps because they are seen as professions that possess no secrets. You put something in the ground, it grows you look at it or eat it. Simple? All gardeners know the fallacy of this view. There is a certain alchemy in the garden and most of that magic goes on in the soil and no garden could be made without it. Whether you are making a new garden or curating an old one you cannot neglect the soil and now is the time to give it your full attention.
What we call soil and the Americans call ‘dirt’ is the product of evolutionary processes. A large component will be made up of the mineral strata that underlies your local area. A geological map of the British Isles makes for fascinating viewing. Our country might be small but beneath our feet are the myriad complexities geology. In my own area the base rock is sandstone which in places comes to the surface in harder outcrops called saddle backs. These are areas of harder stone that have been left proud as the retreat of glaciation gouged out softer areas.
Overlaying the mineral layer is the subsoil which is what you find when you dig down and get past the more organically rich topsoil. The former can be divided into types ranging from clay to sandy. This can affect important matters such as how well water drains away. Too slowly and you end up with problems of water logging. Too quickly and drought can be a real problem in summer. Where clay is a problem the soil can become deficient in oxygen leaving a greyish colour and sometimes a smell of rotten eggs. Above this layer lies the topsoil which can often be distinguished (if you are lucky enough) by colour and texture. A good topsoil will be dark brown to black, crumbly and sweet smelling hopefully with plenty of worms and other organisms. This is where the real magic happens and where most of the roots of any plants will be concentrated. This is because this is where most of the nutrients are concentrated from falling leaves or applied by the conscientious gardener via the incorporation of organic matter or washed in by rain. The actions of fungi, microbes and ‘minibeasts’ such as worms, beetles and the like help break down organic matter into simpler elements that can be taken up by plant roots. It is therefore very important to look
after this layer.
Cover it if it is exposed either with the leaves of evergreen and deciduous plants or with some form of mulch whether that be leaf mould, well rotted manure, straw or chipped bark that has been left to rot at least 12 months. This latter step is quite important as fresh bark can rob the soil of nitrogen. If unsure apply a good application of slow release organic
fertiliser beneath the bark to counteract nitrogen robbery. A good mulch should be as thick as possible preferably six inches thick. This can strain resources for even the most energetic composter so I use a system of rotation by mulching different beds every year. Better to apply a thick mulch to a few beds than an insufficient smattering to all.
Covering the soil with mulch not only suppresses weeds but also prevents the soil from drying out due to the evaporation of water through solar heating or the action of wind. A good covering also prevents compaction which is a major enemy of plants. If a soil is compacted then the roots cannot establish themselves compromising a plants’ ability to find nutrients or water or securely establish itself. Even rain splash can cause compaction to say nothing of heavy footfalls on a soil that is too wet and cold to receive it. This is why gardeners often use boards to get about as they spread the weight and fork over the area they have been working to break up any
Over time the mulch will disappear as it is broken down into its chemical constituents and worked in by worms and other creatures but this should give you enough time to get a respite from weeding and allow plants to establish a better root zone. The addition of bulky organic matter such as manure helps to open up a heavy clay soil allowing water and air to penetrate to lower depths. Where a soil is sandy the addition of the same substance will work the opposite miracle by adding ‘body’ to help retain moisture in dry periods. There is always more than meets the eye whether that be in a humble person or a humble substance.