Natural gardening is about accepting that with the plants you cultivate, you must expect to find a fairly complex insect life co-existing with it. It means that in some years, aphids for example, may be more of a nuisance than in others. In the long run however, natural predators of pests will control their spread. The aim of every gardener should be to control and not to eradicate pests within the garden, which is impossible anyway. The first principle of natural gardening is having healthy plants growing in a healthy soil.
Healthy plants are less likely to be attacked by pests.
Achieve a healthy soil and you will be half way to solving the problem of garden pests. The first step then, is to improve your soil . Use plenty of organic manures and composts . These help to feed the soil and help build up a healthy population of soil organisms, which in turn feed your plants. Avoid artificial fertilisers.