Delving deeper into soil ecology can be a good move for an organic gardener. The more we know about our soil and what it contains, the better placed we will be to manage our gardens in an eco-friendly and sustainable way.
One important soil dweller is one that many gardeners know nothing about. Nematodes are little understood – but they account for around 80% of all individual animals on Earth. More than a million of these tiny, thread-like roundworms are found in just 1 sq m of soil.
If we got rid of all the animals, trees, plants etc. from our planet, but the nematodes remained, we’d still be able to see the shadowy shapes of these former things – made up of these minuscule creatures.
Nematodes are numerous and varied. When it comes to organic gardening, it is important to understand that some are beneficial in our gardens, and some cause problems.
Many nematodes serve important ecological purposes. Some play important roles in the nitrogen cycle, for example. And others regulate the amount of bacteria in the soil. (Some eat up to 5,000 bacteria each minute.
Sometimes, certain nematodes are deliberately introduced to gardens as biological pest control. Pathogenic nematodes, for example, are introduced to deal with pest problems, such as issues with slugs, chafer grubs, sawfly and vine weevil.
However, using biological controls to deal with pests should only ever be a last resort. In an organic garden, the goal should be to create a thriving and balanced ecosystem, rather than trying to eradicate certain species all together.
Not all nematodes play a positive role for gardeners. Some can cause issues with common crops. The potato cyst nematode, for example, can pose problems for a potato crop.
Careful crop rotation and companion planting can help deal with such problems. Planting marigolds is one common solution posed for such problems.
If you would like advice on dealing with nematode problems in your garden, on crop rotation or companion planting – please do get in touch.