Garlic (Allium sativum L.), an important foreign exchange earner, is used as a spice or condiment throughout the country. India ranks second in area and production of garlic in the world. In Kerala, garlic cultivation is confined to Devikulam block of Idukki district and it is cultivated commercially in Kanthalloor and Vattavada panchayats. Singapore, Mettupalayam and Malapoondu are the major local cultivars prevalent in this area. Information on the performance of improved garlic varieties in the high range of Kerala is lacking. Hence, the present study was undertaken with an objective to evaluate the performance of various garlic genotypes for yield and quality in the Kanthalloor panchayat of Idukki district. The experiment was conducted in farmers’ fields of Kanthalloor panchayat during first crop season from May-September 2017. Nine released varieties like Yamuna Safed, Yamuna Safed-2, Yamuna Safed-3, Yamuna Safed-8, Yamuna Safed- 9, Bhima Omkar, Bhima Purple, AAS-2, Ooty-1 and one local cultivar were evaluated for biometric characters and biochemical parameters. In all genotypes, stem colour was yellowish green. Anthocyanin pigmentation at the base of pseudostem was noticed in all genotypes except Yamuna Safed-9, Bhima Omkar and local cultivar. The local cultivar was early in germination (8 days) and also recorded a higher value of Visual Index of Dormancy (80.89%). The field survival per cent at two months after planting was high in Yamuna Safed-9 (97%), Yamuna Safed- 3 (96%) and AAS-2 (96%). At two months after planting, local cultivar recorded highest plant height, leaf width and neck thickness, whereas number of leaves per plant was highest in AAS-2. At the time of harvest Yamuna Safed-3 recorded highest plant height, number of leaves per plant and neck thickness but the leaf width was high in local cultivar. The genotypes AAS-2 and local cultivar had shortest duration of 95 days. White coloured bulbs were observed in Yamuna Safed, Yamuna Safed-8 and Bhima Omkar. In all genotypes bulbs were oval in shape in longitudinal section. The skin colour of clove was cream in general, but it was purple in Yamuna Safed-9 and Bhima Purple and pink in AAS-2. Invariably the clove flesh colour was yellow in all genotypes evaluated. Single clove bulbs were observed in genotypes Yamuna Safed-8, Yamuna Safed-2 and Yamuna Safed (79.16%, 25.17% and 22.26% respectively) which indicate that these genotypes were poor in clove differentiation in the agro ecological situations of Kanthalloor during first crop season. The genotypes local cultivar and Yamuna Safed-3 recorded a high fresh bulb weight (15.66g and 15.31g respectively). The variety AAS-2 recorded highest number of cloves per bulb (16). The number of cloves per bulb in Yamuna Safed-3 (14.47) was on par with AAS-2. The variety Yamuna Safed-3 recorded highest estimated yield per hectare (5.96t) followed by local cultivar and Ooty-1 (4.48t and 4.47t respectively). Fresh bulb weight showed highly significant positive correlation with leaf width, plant girth, plant height, leaf length, equatorial diameter, polar diameter and clove length. The genotypes were grouped into five non-overlapping clusters based on yield and yield attributing characters. The genotypes Yamuna Safed-3 and local cultivar, the high yielders fall in cluster 2 and it has the least distance to cluster 5 which includes Ooty-1. But considering the important yield and quality aspects in trade i.e. yield, fresh bulb weight, clove weight, essential oil content and pungency the local cultivar was found to be the promising genotype over Yamuna Safed-3. But when the genotypes were ranked considering the important yield and quality aspects in trade, the local cultivar was found to be the promising genotype over Yamuna Safed-3.