In 2024, an experiment was conducted on the experimental field of the Biotechnical Faculty in Ljubljana. We looked at the impact of three different substrates on the rooting of leafy cuttings from three selected woody plants: smoke tree 'Royal Purple' (Cotinus coggygria Scop. ‘Royal Purple’), red guelder rose (Viburnum opulus 'Roseum') and higan cherry (Prunus × subhirtella Miq.). We used green, terminal cuttings, 15 cm in length, which were treated at the basal end with a rooting powder containing 0.5 % IBA and 10 % of the fungicide Euparen and planted into three different substrates: pure sand, peat/perlite and peat/sand (both in a 1:1 ratio). Each substrate received 90 cuttings (30 cuttings per species). At the end of the growing season, we evaluated the survival rate, rooting success, root system length and quality, as well as the number and length of shoots. The peat/sand mixture proved to be the most effective substrate. In this substrate, red guelder rose developed the longest roots (21.4 cm on average) and the highest number of roots (34 per plant), while achieving an almost 100 % rooting rate across all substrates. Higan cherry rooted only in the peat-based substrates, with rooting percentages of 50 % in peat/sand and 47 % in peat/perlite. Smoke tree 'Royal Purple' achieved up to 80 % rooting in the peat/perlite substrate but developed a relatively short root system, with an average length of 11.7 cm. The results confirm that rooting success is strogly influnced by plant species, substrate type, physiological age of the cutting and growing conditions.
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