Question

if by adding manure and fertilisers we can replenish the soil so why we have to do fallowing and crop rotation to replenish the soil.

Answer 1

Dear student, we can replenish the nutrients by fertilizers. By following, we allow the weeds to grow out so that we can remove them, which is also part of cultural way of weeding. This also allows the soil to regain its nutrient and fertility. Crop rotation minimises the need of adding fertilizer because nitrogen fixing plants already did that.