Pengaruh Populasi Tanaman Berdasarkan Jarak Tanam dan Waktu Pemangkasan Bunga Terhadap Pertumbuhan dan Produktivitas Kentang (Solanum tuberosum L.)

Abstract

This research was conducted to evaluate the effect of plant population based on planting distance and the timing of flower pruning on the growth and productivity of potato (Solanum tuberosum L.). The study was carried out in Siborboron Village, Sijamapolang Subdistrict, Humbang Hasundutan Regency, North Sumatra, from January to April 2025. The experimental design employed was a factorial Randomized Block Design (RBD) consisting of two factors with three replications. The first factor was planting distance, representing plant population, with three treatment levels: J1 (70 cm × 25 cm), J2 (70 cm × 30 cm), and J3 (70 cm × 35 cm). The second factor was the timing of flower pruning, with five treatment levels: P0 (Control – no pruning), P1 (Pruning at 40 days after planting), P2 (45 days after planting), P3 (50 days after planting), and P4 (55 days after planting). The results indicated that planting distance had a significant effect on several growth and yield parameters. The 70 cm × 30 cm spacing produced the most favorable outcomes in terms of plant height, number of leaves, number of branches, and tuber weight per sample. Meanwhile, the 70 cm × 25 cm spacing was optimal for tuber weight per plot, total fresh weight, and marketable fresh weight. The largest tuber diameter was observed at the 70 cm × 35 cm spacing. The timing of flower pruning also exhibited a significant effect on all measured parameters. Pruning at 40 days after planting resulted in the best performance in terms of plant height, number of leaves, number of branches, tuber diameter, tuber weight per sample, tuber weight per plot, total fresh weight, and marketable fresh weight.No significant interaction was found between planting distance and flower pruning time for any of the observed variables.