Abstract

The use of medicinal plants to treat diseases since ancient times has been applied. Nowadays, the number of the plants used for medicinal purpose is about 35,000 species. In this study, the effect of macro elements (nitrogen, phosphorus and potassium) on the properties of medicinal plants was reviewed. Investigations carried out showed that with adequate supply of N, P and K utilization by various spice crops are enhanced. Macro elements caused increase the number of traits such as plant height, leaf area, yield seed, and oil content. Some of traits of medicinal plants such as basil, turmeric, black pepper, cardamom, fennel, fenugreek, and Aloe vera with used potassium were changed. 
 
Key words: NPK fertilizer, medicinal plants, soil, nutrition.