The study was conducted in Dilla sub-station with objective of identifying optimum between plant space for optimum seed yield and quality seed. One high yielding variety, which is in seed multiplication, was used for the experiment. Four different between plant spaces (10 cm, 20 cm, 30 cm and 40 cm) with constant between row spacing (40 cm) were used as experimental treatments in a randomized complete block design (RCBD) with four replications. The results indicated that dry herbage yield has shown significantly (p<0.05) higher in plant spacing of 20 cm than other spacing (30 and 40 cm) On contrary to herbage yield, at spacing of 30 and 40 cm seed yield was higher than 20 cm spacing. Seed yield has showed statistically significant variation at 30 cm than at 20 and 10 cm between plants spaces at (p<0.05). Hence, there will be two recommendation options for smallholder producers. To secure feed shortage and increased herbage production 20 cm between plant spacing is sufficient while for increased seed yield 30 and 40 cm could be recommended. Further trials might be required in intercropping condition with different cereal crops to utilize resources more efficiently. . Keywords: Biomass yield, seed yield, plant spacing, cowpe
