The growth of technical–scientific knowledge is crucial for the conservation of biodiversity and the sustainable management of endangered species, particularly given the limitations in information about high-performance seedling nutrition. Controlled-release fertilizers (CRFs) have strategic advantages in terms of nutrient use efficiency and less need for reapplications. However, their use in the production of native forest seedlings is still little explored. This study aimed to evaluate the effects of applying CRFs in different doses on the growth and quality of cedro-rosa (Cedrela fissilis Vell.) seedlings, aiming to identify more efficient fertilization strategies in nurseries. The seedlings showed 100% survival at 150 days. The absence of fertilization resulted in limited growth, while increasing doses promoted significant gains. The dose of 16 g L⁻¹ provided greater height and leaf area, while 8 g L⁻¹ was sufficient for gains in diameter and robustness index. There was an increase in dry mass and chlorophylls, although stabilized at higher doses, suggesting physiological limits. Doses of between 8 and 16 g L⁻¹ of CRF are promising to produce cedro-rosa seedlings, combining gains in growth, quality, and physiological efficiency, making it a viable and sustainable alternative.