Farmers have been advised to start the cultivation of bitter gourd (Karela) immediately and complete it by the end of March to get a bumper yield. A spokesman for the agriculture extension department told APP here Saturday that growers should cultivate approved varieties of Karela as these have better disease resistance in addition to give maximum produce. Farmers should use 3.5 to 4 kg seeds per acre, adding that they could contact the agriculture department immediately if they needed any assistance or guidance in this regard.