Vegetables are a common and important source of food and nutrition but the increasing concentration of cadmium (Cd) in the food chain via wastewater-soil-vegetable continuum is posing a threat to their growth as well as human life. This study aimed at determining the effects of variation in duration of plant exposure to different dosages of Cd on growth, physiology and potential health risks of three commonly grown leafy vegetables, viz. spinach (Spinacia oleracea L.), fenugreek (Trigonella foenum-graecum L.) and coriander (Coriandrum sativum L.). The experiment was a 5 × 3 factorial containing five doses (0, 10, 20, 30 and 40 mg Cd kg −1 soil) and three (25, 50 and 75 day) durations of plant exposure. The experiment was laid out in completely randomized design (CRD) with three replications. It was found that plant height, root length, leaf area and biomass were significantly affected by increasing Cd concentration up to 40 mg kg −1 for all the vegetables. Furthermore, Cd treatments significantly affected the photosynthetic and biochemical attributes such as chlorophyll a, chlorophyll b, carotenoids and total chlorophylls at various growth stages of vegetables tested in comparison with their respective controls. Accumulation of Cd in all the leafy vegetables, its daily intake via vegetable consumption and health risk index were significantly increased with the increase in Cd concentration. The highest values of these parameters were found at 40 mg Cd kg −1 soil. It could be concluded that duration of exposure and Cd dose were very important in determining Cd toxicity, which are reflected in drastic reduction in vegetable growth and physiology. Moreover, the consumption of such vegetables would have toxic effects on human health.