This study was conducted for two consecutive years to find optimum onion spacing
under full irrigation, which allows the maximum yield of onion at Kencho kebele of
Uba debretsehay woreda Gofa Zone Southern, Ethiopia through the support of the
Participatory Small-scale Irrigation Development Program(PASID II). The
experiment has four levels of onion planting spacing (8cm, 10cm, 12cm, and
Farmer's practice or planting with own practice), laid down in Randomized
Completed Block Design (RCBD) with four Replications. The same amount of
irrigation water (416.56mm) which is 100%ETc was applied for all treatments in the
five-day intervals during the study. There was no significant difference among
treatment spacing 8cm,10cm, and 12cm on the total yield of onion (16.304
t/ha,17.178 t/ha, and 17.740 t/ha), respectively. The only statistical difference was
observed between the three treatments and farmer practice which is 7.3cm
(11.464t/ha) on average spacing. Accordingly, farmers’ (FREG) were very profitable
from the study in both years. Of course, the yield obtained from the study was very
low as compared to the potential yield of Red Creole variety in Ethiopia. As a result,
farmers were earned a seasonal income of 34ETB/kg which was very costly, and
532,831ETB/ha on average from seasonal production. This implies that low
production potential, but makes high profitable for the farmers during the season. So
the PASIDP has vital economic values on the livelihood of farmers and even good
training for neighborhood farmers. Therefore it was recommended that application
appropriate onion spacing of 10cm with a properly managed field irrigation system
makes it highly profitable with marketable yield under full irrigation (100%ETc).
