Principle 4: Avoid using harmful chemicals

Butterfly

To many people, avoid using toxic chemicals is the most obvious organic gardening practice. In truth, if you follow the other four principles you will naturally find that you neither need nor want to use harmful chemicals in your growing area. However, persistent pest and weed problems may tempt you to reach for the poison.

Here are the two main reasons why not:

  • Pesticides and weedkillers, such as glyphosate, also destroy other life forms. We know that neonicotinoids (used to kill insects) also affect bees and other pollinators, and toxic weedkillers can harm soil life and create residues in the soil.
  • These chemicals can cause serious pollution – either during manufacture or from their own residues.
  • Research suggests that herbicides may become ineffective over time, or if used in large quantities.

The organic gardener should tolerate, not obliterate. For instance, some weeds – such as dandelions – are beneficial to pollinators. Others, such as nettle leaves, provide nutrients for the compost heap and can be used to make organic plant feed. Insect 'pests', such as aphids, are food for beneficial insects such as hoverflies and ladybirds. And even the slug is nutritious for thrushes and ground beetles.