Abstract
Tiger nut is a nutritionally dense crop with various recognised health benefits. Two field trials were conducted in 2023 and 2024 at the University of Abuja Teaching and Research Farm, Nigeria, to assess the influence of organic liquid fertilisers and plant spacing on the growth and yield of two tiger-nut varieties (Kano-Yellow and Borno-Brown). The experiment used a 2 × 3 × 3 factorial in a randomised complete block design with three replications, giving 54 plots. Factors were two varieties, three spacings (15 × 15 cm, 15 × 30 cm, 30 × 30 cm) and two fertiliser treatments (Supergro, Agri‑Life, and a no‑fertiliser control). While variety had no significant effect on most parameters, both fertilisers markedly improved growth: plant height (12.8 cm Supergro, 12.5 cm Agri‑Life at 4 WAP), leaf number (27.3 Agri‑Life at 4 WAP), leaf area (11.9 cm² Supergro, 11.5 cm² Agri‑Life at 6 WAP), net accumulation rate (10.9 g m²/day Supergro at 8 WAP), and biomass (10.9 kg/plot Supergro in 2023). Supergro produced the highest fresh nut count (21.6 nuts/ plant) and the greatest yield at 15 × 15 cm spacing (29.8 t/ha, 2023). Plants at 30 × 30 cm were significantly taller (p < 0.05) and produced more biomass, yet spacing did not significantly affect overall nut yield per hectare. The brown variety yielded higher fresh biomass (7.8 kg/plot), while the yellow variety combined with Supergro gave the best nut count. Significant interactions were observed for variety × fertiliser, fertiliser × spacing, and the three‑way interaction (p < 0.05). For optimal results, farmers should pair a high-density 15 × 15 cm spacing with Supergro organic fertiliser.