Primary propagation methods for oxera include cuttings, division, and seed sowing. Key factors for success are adequate light, warmth, and well-draining soil. Special techniques might involve treating cuttings with rooting hormone and ensuring high humidity levels. The difficulty varies but can challenge beginners due to potential rooting issues and seed viability. Recommended steps: 1) Take semi-hardwood cuttings in spring; 2) Apply rooting hormone; 3) Plant in a suitable substrate; 4) Keep moist and in indirect light until rooted; 5) Transplant carefully after the establishment.