The global usage of pesticides has increased by more than 1.5 times over the last three decades. As a consequence, waters are increasingly contaminated by pesticides and their degradation products. For example, organochlorine pesticides are considered most hazardous due to their long half-lives in the environment, up to 5–15 years, and because they bioaccumulate. This is a major health issue requiring advanced methods for water cleaning such as adsorption with activated carbon, yet actual methods are limited by the cost, poor recyclability and disposal of current adsorbents. Here, we review pesticide adsorbents made of materials. Biochars derived from plant materials show maximal adsorption capacities up to around 900 mg/g due to high carbon content in the range of 38 to 80%. Strategies for field applications and post-treatment of spent adsorbents are discussed.