Surface and subterranean application of five tithonia (Tithonia diversifolia) rates (0.6, 1.02, 1.63, 2.04 and 2.44 t/ha) was made to cotton at the National Semi Arid Resources Research Institute (NaSARRI) in 2014 and 2015. Surface application was accomplished by spreading the different tithonia rates on the soil underneath the cotton crop. Subterranean application was done by making trenches in the ground under the cotton crop followed by burying the tithonia in the trenches besides the cotton rows. Under surface application in 2015, seed cotton yields obtained from the five different rates were 2071.1, 2151.3, 2257.7, 2275.3 and 2639.0 kg/ha respectively compared to 1846.7 kg/ha from the control. As for the subterranean application in the same year, yields were 2295.3, 2361.7, 2375.2, 2913.2 and 2504.7 kg/ha respectively compared to 1289.7 kg/ha from the control. Yields of 2014 were lower but the trends were similar. Yield responses under surface tithonia application increased linearly with increased rates, while under subterranean method, the peak was at 2.04 t/ha rate. Subterranean application in 2014 significantly (P=0.05) increased cotton fibre length and strength compared to the controls. The longest (27.12 mm) and strongest (29.7 g/tex) fibres were recorded from cotton that received 2.04 t/ha of tithonia compared 25.47 mm and 25.8 g/tex respectively from the no-fertilizer controls.