Valerian and Yarrow: Two medicinal Plants as Crop Protectant Against Late Frost

Abstract

Valerian (Valeriana officinalis L.) and yarrow (Achillea millefolium L.) are well-known medicinal plants that have been widely used in Europe and Asia. In addition to their therapeutic effects, they turn out to be efficient in crop protection. Indeed, extract of their aerial parts are useful in preventive treatment against late frost damages on grapevine, fruit trees and various vegetables. The French Technical Institute of Organic Farming (ITAB) is working for their approbation by the European Union as “basic substance”, according to provisions laid down by EC Regulation 1107/2009 on placing plant protection products on the market. Basic Substances represent a new category of plant protection in the European Union. Therefore, a review of available literature was carried out to collect data on their application in plant protection and their toxicological effects. Studies and testimonies showed that valerian and yarrow mixture is efficient in plant protection and the two plant extracts are not of concern.