The yield of cowpea (var. IT99K-573-1-1) was tested in a field experiment using 12 different weed control treatments during the wet seasons of 2019 and 2020. The results showed that hoe weeding at 3 and 6 WAS had the highest weed persistence index, crop resistance index, and agronomic management index, closely followed by pendimethalin 2.0 kg a.i.ha-1 fb SHW at 6 WAS, and metolachlor 2.0 kg a.i.ha-1 fb SHW at 6 WAS. The most effective phytotonic practices were hoe weeding at 3 and 6 WAS, pendimethalin 2.0 kg a.i.ha-1 fb SHW at 6, and metolachlor 2.0 kg a.i.ha-1 fb SHW at 6. The best weed control methods for cowpea production from environmental point of view, were metolachlor at 2.0 kg a.i.ha-1 fb SHW at 6 WAS and pendimethalin at 2.0 kg a.i.ha-1 fb SHW at 6 WAS. Lower persistence of escaped weeds were seen with pendimethalin at 2.0 kg a.i.ha-1 fb SHW at 6 WAS and metolachlor at 2.0 kg a.i.ha-1 fb SHW at 6 WAS, indicating that these treatments had a broader weed-controlling impact than the other treatments.