Garlic (Allium sativum L.) is one of the most important food products in the world and an ancient and widespread medicinal herb. It is rich in minerals and vitamins, which are both essential nutrients for human health. This study was carried out on four traditional landraces of garlic: Rosso di Sulmona, Rosso di Proceno, Bianco Piacentino, and Rosso di Castelliri, all cultivated with the same agricultural practices in two different areas of the Lazio region. The aim was to study the effects of both production soil and genetic characteristics on the concentrations of certain micronutrients in these garlic bulbs. The content of minerals and trace elements (Ca, K, P, Mg, Na, Fe, Zn, Cu, Mn) was determined via ICP plasma after liquid washing. Water-soluble vitamins (riboflavin, niacin, thiamine, B6, vitamin C) were evaluated using an HPLC and UV detector. Among the minerals identified, potassium was most represented, with a value ranging between 645 and 1057 mg/100 g d.w., whose content is influenced by the interaction between cultivars and cultivation area, suggesting that pedoclimatic and genetic characteristics determine this content. Among vitamins, vitamin C was found to be most represented, with an amount that varied from 9.7 to 15.6 mg/100 g f.w. and did not depend on the cultivar or the geographical area. Among the B vitamins, the most abundant was vitamin B6, the maximum content of which was found in the Rosso di Castelliri cultivar grown in Viterbo (2.04 mg/100 g f.w.). Its concentration is influenced by the cultivar and the soil and their interaction. The results obtained showed good levels of essential micronutrients and highlighted that for some of them, the effect of soil typology is expressed in the presence of specific characteristics linked to the genotype.