In citrus orchards weed control is carried out by 2 or 3 cross ploughing. While resorting to manualweeding tillage should not be deeper than 10 to 15 cm. Deep tillage once or twice in a year is more harmful than regular deep tillage. Diuron at 3 kg/a.i. /ha or Simazine (4kg a. i./ha) when sprayed during end of May controls dicot and monocot weeds in the orchard. The application may be repeated at 120 days for complete control of the weeds.
The inter spaces between the rows can be utilized in the initial 3 - 4 years for growing short term crops like Mung, Black gram, groundnut, soybean and vegetable crops. During the rainy season green manuring crops are grown and plowed into the soil before flowering. The choice of inter crop depends on local condition and climate. However indiscriminate cultivation of exhaustive inter crop should be avoided. Inter cropping in Nagpur mandarin plantation should be avoided as it increases pest and disease incidences and even micro nutrient deficiencies.
Training and Pruning
In Citrus pruning is done to develop a strong framework in the beginning. Branches growing up to 45 cm from the ground are removed leaving a clear straight stem. 4 or 5 well-spaced branches are retained forming a thick bushy crown, which protects the stems and branches from the effects of sunshine.The bearing trees require support, as due to heavy bearing the branches tend to break. Usually the support is given by erecting a bamboo frame around the plant at a height of 2 - 2.5 m and the branches are tied with the help of rope to the structure.
Regulation of Flowering (Bahar Treatment)
Due to the absence of low temperatures in Central India, The natural flowering of citrus trees is of very less intensity. Therefore the flowering is usually forced by withholding irrigation water.For forcing the trees to flower during February-March (ambebahar), the water supply to the trees is with held for 40 to 60 days, i.e., from 15th November to end of December until the leaves show symptoms of temporary wilting.For mrigbahar (July flowering), about 40 to 50 days water stress (25% leaf drop) during May-June is sufficient to force the trees to flower.