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The study was conducted between 2023 and 2025. The effectiveness of various auxin-containing growth stimulants was investigated in the rooting of semi-lignified cuttings of blue spruce (Picea pungens Engelm. f. glauca). The relevance of the work is due to the low natural ability of cuttings of this species to form adventitious roots and the limited scientific data on the use of commercial preparations based on indolyl-3-butyric acid (IBA) and naphthylacetic acid (NAA) in coniferous ornamental nurseries. Planting was carried out in a substrate consisting of a mixture of sand and high-moor peat in a 1:1 ratio. Each research variant had four replicates of 30 cuttings. The experiment used Rhizopon 0.2%, Rhizopon 0.3%, and Rhizopon 0.5%, the main active ingredient of which is IBA, as well as aqueous solutions of NAA in concentrations of 1000, 3000, and 5000 mg/l. Control cuttings were rooted without the use of growth stimulants and were soaked in water. It was found that the use of Rhizopon 0.3% provided the highest efficiency of rhizogenesis: the average number of rooted cuttings over three years was 10.33 of the total number of cuttings, or (34.4%), which significantly exceeded the control, more than six times, where the number of rooted cuttings ranged from 1 to 2 and the average value was 1.66 cuttings or (5.5%), and the result of using Rhizopon 0.3% exceeded the other variants of the experiment. When using Rhizopon 0.2%, the average rooting rate was 7.66 cuttings, which is 25.5%, while Rhizopon 0.5% reduced this rate to 3.66 cuttings, which is 12.2%, indicating the inhibitory effect of the preparation. Among the options with NAA, the highest efficiency was found at a concentration of 1000 mg/l, where the average number of rooted cuttings was 6 or (20%), while at concentrations of 3000 and 5000 mg/l, the efficiency decreased sharply and approached the control values. Accordingly, 3.66 cuttings (12.2%) rooted when using a NAA concentration of 3000 mg/l and 1.33 cuttings (4.4%) rooted when using a NAA concentration of 5000 mg/l. The results obtained make it possible to justify the optimal options for the use of Rhizopon and NAA preparations for practical use in the production of Picea pungens f. glauca planting material.