Bacteria are all around us, all the time. If we think of them at all, we tend to think of those bacteria which can do us harm and make us sick. But bacteria do not only pose a problem to human health – many bacteria are also beneficial, aiding us in a number of different ways. In our gardens and polytunnels, for example, we cannot see them, but bacteria are a crucial part of our food-growing ecosystems.
How Can Bacteria Help You in The Garden?
Living in the root nodules of plants, and in the soil, different bacteria make our growing efforts possible. Without them, ecosystems and natural cycles could not function. In order to make the most of our polytunnels, and in order to grow our own food successfully, it is important to make sure that we allow these bacteria to do their jobs. A basic understanding of how bacteria help us as polytunnel gardeners can be useful. Caring for soil bacteria and other biotas can help us make the most of the growing space at our disposal.
Bacteria in the Soil Ecosystem
- Nitrogen Fixing Bacteria in Root Nodules. Bacteria living in the root nodules of plants such as legumes (peas, beans etc.) and other nitrogen fixers help transfer atmospheric nitrogen to the soil, where it can be taken up by other plants.
- Nitrogen Fixing Soil Bacteria. Other nitrogen-fixing bacteria present in soil also fix nitrogen from the air.
- Aerobic and Anaerobic Decomposers. Meanwhile, bacteria are also amongst those organisms which help to break down rotting plant and animal waste material in a process known as ammonification.
- Nitrifying Bacteria. Nitrifying bacteria take the Ammonium created by nitrogen fixing and decomposing bacteria and turn it into Nitrites and then to Nitrates – the form in which nitrogen can be taken up by plants.
- Denitrifying Bacteria. Denitrifying bacteria complete the cycle by returning nitrates to the air in the form of atmospheric nitrogen.
The Pros of Bacteria
The bacteria involved in the nitrogen cycle are just some of the many beneficial bacteria found in our polytunnel gardens. Bacteria also promote nutrient mineralisation and availability, produce plant grown hormones, and are antagonists for pests, parasites and diseases. Beneficial bacteria can play a huge role in the immune system of plants. Bacteria can also break down pesticides and pollutants… Bacteria present in soil have even been shown to promote human happiness and well-being – acting on our serotonin receptors!
A ton of microscopic bacteria may be active in each acre of soil. A teaspoon of soil generally contains between 100 million and 1 billion bacteria! Bacteria are more important than most polytunnel gardeners realise. It is vitally important that we allow such beneficial bacteria to thrive. We can do this in a few ways:
- through practising organic gardening methods
- ‘no dig’ systems
- incorporating plenty of organic matter
- allowing the ‘soil food web’ to thrive.
Elizabeth Waddington is a writer and green living consultant living in Scotland. Permaculture and sustainability are at the heart of everything she does, from designing gardens and farms around the world, to inspiring and facilitating positive change for small companies and individuals.
She also works on her own property, where she grows fruit and vegetables, keeps chickens and is working on the eco-renovation of an old stone barn.