Already a third of the world's soils are significantly degraded. There are several reasons for this, but mismanagement by man is top of the list!
To feed a growing population, we need to treat our soils better now and in the future! So why have soils become so degraded, and what can we do about it? Find out all the information about soil you could ever need in the articles recommended at the bottom of this article.
Intensification of cropping
- While growing crops intensively is not necessarily harmful, doing so without care of the soil certainly is.
- We should maximise the best soils in the world - and our gardens - to produce crops. But bear in mind that these soils are finite and have taken millennia to create so should be treated delicately.
- There can be no doubt now that our climate has changed and become much less predictable.
Joe Swift and Ali Vowles filming Gardeners World in a downpour
- We are already experiencing more extreme weather conditions, and this makes managing our soils more challenging but also more essential than ever.
- Heavy rain falling onto bare soil often leads to surface runoff.
Tree roots washed out due to soil erosion
- Ensuring that your soil is covered when heavy rains are more likely to occur (autumn and spring) will minimise the risk of soil erosion.
- On the East Anglian Fens - an intensive vegetable production area - soils are still being lost by simply blowing away! These light, peaty soils are easily blown away when not covered by a crop.
- In your garden, soil erosion can be prevented by covering the soil with an organic mulch between crops or by adopting a 'no-dig' approach for vegetable growing.
- The soil that is lost through runoff is invariably from the top-most layer, and it is this soil that is most productive.
- Soil erosion from rainfall is most likely to occur on sloping sites, so it pays to cultivate across - rather than up and down - any slopes you're working on.
- Organic matter in the soil breaks down over the years and will need to be replaced once it has been used up.
- Organic matter makes soils more crumbly and open to both water and air.
Composted green garden waste on an industrial scale
- Heavy rainfall is much more likely to soak into the soils with higher amounts of organic matter and less likely to wash away the soil surface.
Loss of soil life
- As we've seen, soil is much more than a handful of dirt! There's a lot of life in productive soils, and we need to look after it.
- The addition of composted plant material will feed these soil organisms and keep our soils fertile and healthy.
- Floods and rivers deposit soils, leading to some of the world's most productive land. Silt soils in broad river deltas are a prime example.
- However flooding, whether due to exceptional rainfall or rising tides, is now becoming commonplace.
- On a small scale, it might seem that gardeners are powerless to prevent this. However, one of the key contributors to flooding in towns and cities is undoubtedly the replacement of gardens with impermeable surfaces.
Paved front gardens contribute to flood risk
- So-called 'rain or 'sink gardens' are a practical measure that gardeners can take to slow down the runoff of rainwater from gardens. These allow time for the rain to soak into the soil rather than flooding the public drains and roads.
- The plants you choose to go in a rain garden should be able to tolerate flooding for up to 48 hours. This lends itself to flower gardens rather than any edible plants.
- Cultivating vegetables, herbs, flowers and fruit in raised beds has become very popular.
- Raised beds have wooden sides that protect the soil from erosion.
A raised bed
-This technique enables us to concentrate our efforts on caring for and improving an intensively cultivated piece of our garden.
Timing of cultivations
- Soils can be damaged by cultivation at the wrong time or through careless practices.
- Soils with a high percentage of sand or organic matter can be cultivated just a few hours after heavy rain. But this doesn't apply to all soil types.
- Soils made up of mostly clay or silt will be tough to cultivate when very wet or very dry. You'll need the help of good weather!
- Trying to cultivate a soil when it is too wet leads to damaged soil structure, which in turn leads to that soil becoming even more difficult to cultivate in the future.
Digging soil at the right time