Plant growth-promoting bacteria (PGPB) are beneficial microbes that enhance plant growth and protect plants from abiotic and biotic stresses. The use of PGPB in sustainable agriculture is increasing. However, fewer studies have been conducted in viticulture. Therefore, this study aims to investigate the presence of drought- and salt-tolerant PGPB in vineyard soils, with the potential to use them as biofertilizers in the future. Bulk soil, rhizosphere soil, and grapevine root samples were collected from vineyards in Mildura, Gol Gol, Robinvale, and Piangil in Australia, and microbiological parameters such as colony counts and types were analysed. The growth of morphologically different bacteria at various concentrations of NaCl (for salinity) and polyethylene glycol 6000 (for drought) was assessed using spectroscopy-based turbidity measurements. Then, plant growth-promoting properties of drought- and salinity-tolerant bacteria were evaluated. Positive bacteria were introduced to tomato seedlings grown in Murashige and Skoog medium under controlled conditions, and growth was measured after three weeks. Most of the isolated bacteria were from the rhizosphere, and they were less tolerant to salinity than to drought. Plant growth-promoting properties such as 1-aminocyclopropane-1-carboxylate deaminase production, nitrogen fixation, siderophore production, indole-3-acetic acid production, and acid and base production (except for phosphorus solubilization) were observed in these bacteria. Only 10% of the 60 bacterial isolates with different morphologies exhibited more than one plant growth-promoting character. Tomato plant root length was significantly affected by PGPB application; however, there was no significant difference in shoot length among them, and no correlation was found between shoot and root length. In conclusion, the application of PGPB resulted in differences in root growth during the early vegetative stage of the tested plants. The library of phenotypes will undergo further testing to assess their relationship with plant growth promotion with different stresses, aiming to produce biofertilizers.