It is known that natural and technogenic radionuclides (RN) along the biogeochemical chains of agrocenoses can enter the human body through irrigation water-soil-plants, as well as through nutrientsolution-substrate-plants in a hydroponic system, leading to the development of dangerous diseases. Monitoring and obtaining radioactively safe medicinal raw materials are priority issues. Research has been conducted in the Ararat Valley and at the Dilijan Forest Experimental Station (DFES) since 1996 to understand and control the levels of radionuclides in water, soil, and plant ecosystems. The investigations of RN in agricultural ecosystems are important because they can lead to the development of protection measures to be used in polluted areas and improve the safety of agricultural products. The radio-chemical studies have shown that certain medicinal plants, such as Eleutherococcus senticosus, Withania somnifera, Rosmarinus officinalis, Lavandula angustifolia, and Cichorium intybus, cultivated in outdoor hydroponics and soils of Ararat Valley and DFES, have gross β-radioactivity levels that do not exceed the threshold of 1.0 Bq/g, making them radioecologically safe for use as medicinal raw materials. The research demonstrates that E. senticosus grown in the conditions of the biogeocenosis of the DFES accumulated two times less RN in its leaves than it did in the hydroponic vegetative vessels situated in the Ararat Valley. Medicinal plants grown in hydroponics and soil show a similar gross β-radioactivity decreasing pattern, with only slight deviations, as follows: W. somnifera > L. angustifolia > C. intybus > R. officinalis > E. senticosus. The content of controlled technogenic RN ( 90 Sr, 137 Cs) in natural waters, soils, and medicinal plants of the Ararat Valley and DFES did not exceed the maximum allowable concentrations (MAC).