Overzealous and indiscriminate use of many synthetic pesticides during recent decades in the control of plant pests has resulted in a number of environmental and toxicological problems. Reducing the release of synthetic chemicals into the environment requires that alternative sources of chemicals are developed that can be used safely in the management of plant pests. Botanical antimicrobials derived from plants are currently recognized as biodegradable, systemic, eco-friendly and non-toxic to mammals and are thus considered safe. Their modes of action against pests are diverse. Natural compounds are well suited to organic food production in industrialised countries and can play greater roles in the protection of food crops in developing countries.