Maximizing yields and economics by supplementing additional nutrients for commercially grown menthol mint (Mentha arvensis L.) cultivars

Abstract Supplementation of nutrients plays a vital role in the growth yields and quality attributes of the crops. An experiment and demo trials were conducted in CSIR-Central Institute of Medicinal and Aromatic Plants (CIMAP) research farm and at farmers’ field(s) simultaneously, to study the adequacy of additional nutrients application in menthol mint (Mentha arvensis L. cv. Kosi and Kranti) for improving productivity and profitability. Results of both trials clearly indicated that NPK (recommended dose) and micronutrients based fertilizers eventually leads to accrue the net income. Commercially grown menthol mint farmers benefitted by consequently improvising fresh herbage, oil content, oil yield, gross returns, net income and benefit-cost ratio (B:C ratio) (50.86%, 3.45%, 55.04%, 55.04%, 207.80%, and 50.75%, respectively in cv. Kosi) in treatment T4 [NPK (100:60:40 kg ha−1) + ZnSO4.7H2O @ 25 kg ha−1)] concerning the recommended dose of NPK fertilizers T1 [NPK (100:60:40 kg ha−1)]. Simultaneously, for the second demo trial, conducted in the farmer’s fields, forty two farmers were selected for the cultivation of menthol mint. From the results, it was revealed that recommended dose of NPK fertilizers with the addition of zinc sulphate found significantly maximum yield and net returns in the plots; an increase of oil yields, gross returns, net income, and B:C ratio was 37.05%, 37.05%, 111.18%, and 32.88%, respectively in T2 [NPK (100:60:40 kg ha−1) + ZnSO4.7H2O @ 25 kg ha−1)]. Data attained from soil analysis distinctly showed that moreover increasing the yields and return of menthol mint cultivation, the integration of vermicompost, macro-micro nutrients, and bio inoculants with the recommended dose of NPK remarkably upgrades the soil fertility status in terms of organic carbon, available N, P, and K.