Cocopeat is the most widely used substrate in soilless cultivation because of its high porosity and water retention capacity. However, its high import cost and limited availability highlight the need for sustainable, locally sourced alternatives. This study investigates the physicochemical, biological, and agronomic performance of a palm‑based substrate “palm‑peat” produced from date-palm residues and sugarcane bagasse as a potential substitute for imported cocopeat. The residues were processed through controlled washing, partial alkalization, and mechanical defibration to produce the final substrate. Comparative analyses with imported cocopeat included physicochemical properties (pH, electrical conductivity, bulk density and porosity), biological resistance (mold grown tests), and plant performance tests (germination rate, root–shoot growth, and leaf nutrient content). Each treatment was tested on 30 seedlings with three replicates in a randomized experimental design. Palm-peat exhibited physicochemical values within suitable horticultural ranges (pH 5.8–6.1; EC 1.2–1.4 dS m⁻¹; porosity> 85%), similar to those measured for imported cocopeat. Germination rates exceeded 80% in palm-peat based substrates. Root and shoot development were statistically similar to cocopeat (p < 0.05). Elemental analysis showed that palm-based substrates contained moderate levels of essential nutrients, including K, Ca, and Fe. Their physical performance was comparable to imported cocopeat. Processed palm-peat demonstrated strong resistance to fungal colonization and structural degradation. Overall, the results indicate that palm-peat can serve as an effective alternative to imported cocopeat under the tested conditions. Its utilization promotes circular bioeconomy by valorizing local agro-industrial residues while maintaining plant growth performance in horticultural systems.