A Randomized Complete Block Design Study to Evaluate the Effectiveness of Humic Acid on Growth and Productivity Thymus vulgaris L.

Thymus vulgaris is a versatile plant with various medical and pharmaceutical applications. Thyme has significant antioxidant and antimicrobial properties, and the leaf oil extract shows various medicinal and therapeutic effects. The type of fertilizer and the method of its application can affect the growth and productivity of the thyme crop, which affects the essential oil content. In order to know the effect of humic acid on the growth and productivity of common thyme, a field experiment was conducted in the Qutaylibiyah area, Jableh, Syria, during the agricultural season 2023-2024. The spraying was done with three concentrations of potassium humate solution with the trade name POWHUMUS® WSG 85, which contains 60% humic acid. The experiment was designed according to a randomized complete block design (RBCD) with five replicates for each treatment. The results of the study showed a significant effect of humic acid on all the studied traits. The 200 mg. L-1 concentration was significantly superior to the rest of the concentrations in the traits of plant height (28.15 cm), fresh weight (42.50 g), dry weight (11.75 g), and vegetative production (5.05 tons/ha), the percentage of Essential oil in the leaves (5.75%), and the concentration of 100 mg. L-1 was significantly superior to the control in all the studied characteristics. The study recommends the importance of using humic acids in improving the growth and productivity of medicinal and aromatic plants.