One of the major problems in agricultural production is the control of various pests and diseases that can cause significant damage, and thus reduce or destroy the expected yield of agricultural crops. To successfully deal with these problems, farmers use different types of pesticides. Due to the growing concern for the protection of people and the environment, the number of active substances is reduced, and new active substances are formulated that are less harmful to the environment and users. Therefore, farmers are looking for additional opportunities and solutions in the fight against pests and diseases. Recently, new preparations marked as basic substances have appeared on the EU market, which can be used as additional solutions in the fight against pests and diseases. Legislation, through EC Regulation 1107/2009 at the EU level, sets a quality framework for the safe and efficient use of basic substances in agricultural production. An additional advantage of the application of most of these basic substances is their compliance for use in organic agricultural production. Although there are more than 20 different basic substances used, the most commonly used are liquid extracts of nettle (Urtica spp. L.) and horsetail (Equisetum arvense L.), as well as chitosan hydrochloride, soy lecithin and sodium hydrogen carbonate.