This study aimed to evaluate the effects of synthetic and natural plant growth regulators on the growth of wax apple (Syzygium samarangense) shoot cuttings and to determine the most effective treatment. The experiment was conducted from January to March 2026 in Siabu Village, Mandailing Natal Regency, North Sumatra, Indonesia. A completely randomized design (CRD) with seven treatments was employed, consisting of a control, Rootone-F at 100, 200, and 300 ppm, and shallot (Allium cepa L.) extract at concentrations of 25%, 50%, and 75%, with four replications each. The observed parameters included survival percentage, shoot height, number of leaves, primary root length, and number of primary roots. Data were analyzed using analysis of variance (ANOVA), followed by Duncan's Multiple Range Test (DMRT) at the 5% significance level. The results showed that both synthetic and natural plant growth regulators significantly improved all observed growth parameters compared with the control. The application of Rootone-F at 300 ppm produced the best performance, with a 95.00% survival rate, shoot height of 13.45 cm, 8.75 leaves, primary root length of 12.75 cm, and 14.75 primary roots. Meanwhile, 75% shallot extract produced growth responses comparable to the best treatment, indicating its potential as an economical and environmentally friendly natural plant growth regulator. Therefore, Rootone-F at 300 ppm is recommended as the most effective treatment for improving the propagation success of wax apple shoot cuttings.Abstrak ditulis secara ringkas dan faktual dalam bahasa indonesia dan bahasa inggris. Abstrak sekitar 150-250 kata. Abstrak harus menyatakan secara singkat masalah, tujuan penelitian, metode penelitian, hasil utama dan kesimpulan utama. Abstrak harus ditulis sebagai paragraf, tidak adanya referensi dan singkatan yang tidak standar. Keyword : Rootone-F, shallot extract, shoot cuttings, wax apple, plant growth regulator