Among vegetables, garlic is most susceptible to genetic erosion due to no sexual reproduction. Purpose. To evaluate the genotypic and phenotypic diversity of local forms of spring garlic in the forest-steppe of Ukraine in order to identify valuable specimens for the following characteristics: yield, adaptability, and essential oil content. Methods. In 2018–2022, 12 local and introduced forms of spring garlic were studied in the field. To analyze the data obtained, regression analysis was used to determine the stability and plasticity of the cultivars. Results. The variability of the spring garlic bulb weight was medium (CV = 13%), however, in some accessions, this characteristic varied from 12% to 37 %. Accessions 'No. 33', 'No. 44', and 'No. 55' had significantly greater bulb weights than the mean value: 27.01–28.84 g (+11.9–19.4 % to Xmed). Analyzing the number and size of cloves in the bulb, we selected accessions 'No. 14' and 'No. 33', which had the smallest total numbers of the largest cloves. In general, the clove distribution in the bulb was as follows: 56% of small cloves, 39% of medium-sized cloves, and only 5% of large ones. That is, in the studied sample, there was no accession with a preponderance of large or medium-sized cloves. By essential oil content, the studied accessions were categorized as food cultivars with a minimum content of 0.220–0.253 mg/100 g ('No.', No. 14', 'No. 52', ' No. 53', and 'No. 54') and technical ones with a high content of 0.370 and 0.373 mg/100 g ('No. 43' and No. 57', respectively). By yield, 'No. 33', 'No. 44', and 'No. 52' stood out, yielding 8.94, 9.95, and 9.07 t/ha, respectively, which was statistically significantly more than Xmed by 18.7, 32.2 and 20.4%, respectively. Statistical analysis showed that 'No. 14' was the most stable in terms of this characteristic, while the other accessions were characterized as unstable with bi > 1 and σ2d > 0. The results of statistical processing showed that the phenotypes (CVp) of the studied traits in garlic were characterized by high heritability, which was changeable and depended on environmental conditions (CVe) to a greater extent than on genotype (CVg). Conclusions. Our study is an example of a description of the variability of local spring garlic cultivars and an approach to quantification of local adaptation that currently contributes to their preservation.