Natural Pest Control

Many vegetables grow well with other plants in the garden and, using a few basic principles, organic gardeners can really have nature on their side in the biological control of pests.

How can you control pests and diseases naturally?

The best way to control plant diseases is to prevent them occurring in the first place. This can be achieved with healthy cultivation methods:

Choose plants that match your garden’s conditions and are pest-resistant.

Water to encourage strong root systems and avoid humid conditions. That is infrequent deep watering in the early or late part of the day. Less water on the surface means roots have to search.

Add organic matter to soils as manures, composts and mulches - to encourage microbes that attack plant pathogens and to supply nutrients to plants keeping them vigorous and healthy.

Use seaweed and fish emulsions to boost the plant's immunity to pest and disease attack.

Fertilise to strengthen plants eg. ensure plants have adequate potassium (promoting thick cell walls).

Plant to encourage predators and plant decoys to distract pests. For example mulberries encourage wasps and hibiscus will distract stink beetles from citrus,

Try some companion planting.

The most commonly documented companion plants repel pests when planted alongside vegetables. Other plants attract pest predators to the vegetable patch. Some plant roots secrete substances that repel pests or provide nutrients to the plants around them. These plant interactions can work in specific ways between two or three types of plants or species.

Legumes (peas, beans, etc.) trap nitrogen from the air with nodules on their roots. When these crops have finished producing you can dig them into the soil so that the nitrogen is available to the next crop. Being leafy vegetables, the brassica family (cabbages, broccoli, etc.) require a lot of nitrogen to grow, so it makes sense to follow summer pea crops with winter cabbages that can use this free nitrogen source.

What if pests still invade?

I find it relaxing to spend a few minutes in the garden checking each plant for eggs or pests, if all else fails neem oil is a good organic spray that will help with pests and also fungal diseases.