In this article we will discuss about the orchard cultural practices of mango.
1. Irrigation:
Amount and frequency of irrigation to be given depends upon the type of soil, climatic condition especially rainfall and its distribution and age of trees. The irrigation requirements of young and non-bearing trees are different from those of the bearing trees.
The young non-bearing trees need to be irrigated more frequently in order to grow vigorously and rapidly. The newly planted young mango plants, upto their first four to six months should receive irrigations twice a week in the hot weather. Therefore, the interval of irrigation as well as quantum of water per irrigation may be progressively increased. For the first four to five years, the irrigation must be frequent and regular though of light intensity. During rainy season interval may be adjusted keeping in view the intensity of rainfall and its distribution.
In bearing trees, during the period of two or three months preceding flowering season, profuse irrigation is inadvisable. For the rest of the year, a mango tree should receive irrigation according to its needs which in turn would depend upon several factors such as soil structure, climatic conditions, variety and rootstock and age of the trees. In lighter soils, more frequent irrigation would be necessary than in case of heavy soils.
Similarly, irrigation needs during hot, dry and windy weather will be heavier than in rainy and cold weather. The bearing trees with well-developed root system usually require irrigation during the fruit development period between April to June at an interval of 10-12 days depending upon the evapo-transpiration. One irrigation should be given at the time of addition of fertilizers in the month of February. No irrigation should be given for a period of 2-3 months during October-December.
Generally intercrops are grown during the early years after plantation and hence method of application has to be adjusted accordingly. Upto 5 years, after planting, it is better to make basins around the plants and connect them in series so that irrigation could be administered independent of the intercrop. For subsequent age, irrigation can be combined with that of intercrops. However, if intercrops are to be abandoned in fully- bearing orchards then basin system should be followed so as to economise on the water use. Then the basins may be connected in series or to a channel dug in between the rows.
2. Intercropping:
During the first few years of their non-bearing life and until the trees have grown to a big size, the vacant land in between the mango trees can be profitably utilized for the cultivation of harmless types of intercrops like fodders, farm crops, vegetables and pulses preferably of leguminous type. Intercropping should always be judicious and needs of the trees should receive primary consideration; otherwise the practice may prove extremely harmful.
Intercropping helps to keep the weeds under check, which otherwise would rob the orchard soil of plant nutrients and moisture. Vegetables like onion, tomato, radish, beans, cauliflower, cabbage, leafy vegetables and leguminous crops like moong, mash, gram and lentil can be grown in pre-bearing orchards. Crops like maize, sugarcane and bajra should not be grown in mango orchard.
While intercropping, the trees should be provided with suitably wide basins and an independent irrigation system. They should also be given regular hoeings and weedings. When the trees grow up to a big size, as it usually happens after their 10-12 years of life, then discontinue the intercropping as at that stage it would impair with their normal growth and fruiting.
In order to replenish the organic matter content of the soil, green manuring with leguminous crops like guara, hemp and senji may be carried out, depending upon the need of the soil. Instead of intercropping, temporary quick growing fruit trees can be grown as fillers which are removed when the mango trees assume big size. Papaya, peach, plum, guava and phalsa are grown as fillers. Separate arrangements for manures, fertilizers, irrigation and inter-culture should be made for the inter-plants and intercrops.
3. Inter-Culture:
Inter-culture of the mango orchards is necessary not only to remove the weeds which compete for water and nutrients but also to ensure aeration which is so essential for the proper development of roots and shoots. Hoeing also serves the purpose of mulching and thereby reduces the frequency of irrigation. Inter-culture may help in reducing the insect-pest population by killing them physically.
Frequency and the time of intercultural operations will vary with age of the orchard. If the intercrops are not being raised in the pre-bearing stage due to some reasons, then area in between the basin should also be ploughed atleast three times in a year i.e., pre-monsoon, post- monsoon and in the last week of November.
For the bearing mango orchards, inter-culture is also equally important. First cultivation should be done before the onset of rains. This help in checking run off losses and facilitate maximum intake of water into the soil. Orchard may be ploughed again after the rainy season is over so as to suppress the weed growth and also to break capillaries. Third cultivation may be done in the last week of November or first week of December in order to check the population of mango mealy bug.
4. Manuring and Fertilization:
Although mango grows well even in poor soils because of its deep root system but keeping in view the vegetative growth it has to attain and removal of nutrients through the harvest, it needs some amount of fertilizers. Nutrition requirements may vary with the region depending upon the type of soil and age of the tree. The underfed and under-nourished trees fail to give satisfactory bearing of fruit.
The life cycle of the mango can be divided into five parts, viz. nursery stage, establishment in the field and non-bearing, bearing and a gain period of trees.
Generally, it falls under two main categories viz. non-bearing and bearing stages, while the chief requirements in pre- bearing age are a rapid growth and the development of a strong framework, during the bearing periods good cropping, regular bearing and high quality of fruit are the primary objectives. Nutritional requirements of the trees at different stages, therefore, vary a great deal and are discussed below separately.
(i) Non-Bearing Trees:
This stage extends from the planting of a tree in the orchard until it begins to yield fruits. The manurial programme during this period has to be designed in such a manner so as to achieve speedy development of the tree together with formation of strong limbs and sound framework. The young trees in this stage need to be given liberal doses of nitrogen, calcium and phosphorus.
Potassium would also be needed in reasonable amounts. In soils where calcium content is inherently high and which have a pH ranging from 7.0 to 8.0, the surface application of calcium may not be necessary but in soils where pH is low, ranging in between 5.5 to 6.5, it may be necessary to add calcium through dolomitic lime. The quantities required to be applied would depend on soil reaction and in certain cases may run as high as 2 quintals per acre.
During the non-bearing period, nitrogen is particularly needed in rather heavy quantities to support healthy and fast growth. It would be advantageous to apply substantial portion of N in the form of organic matter, so that texture of the soil, its moisture holding capacity and ultimately the development of roots therein may be improved. Phosphorus would be needed to cope with high respiration rates and for translocation of carbohydrates. Potash would also be required to meet the need of photosynthesis.
The above different needs can be met roughly if N, P and K applied at the rate of 50-100, 40-80 and 100-200 g of actual nitrogen, phosphorus and potash for each year age of the tree with 40 to 80 per cent derived from organic source.
(ii) Bearing Trees:
During this stage the manurial programme should aim at two fold objectives, viz.:
(a) To maintain optimum vegetative growth from year to year, and
(b) To ensure regular cropping with superior quality fruit.
In mango, which is a terminal bearer, the fruit-bud differentiation under most situations takes place about four to five months before flowering. There is an antagonism between growth and fruiting in the tree. In the year of heavy flowering and fruiting the vegetative growth remains suppressed which in turn affects adversely next year’s crop. If the early flush of vegetative shoots does not come up due to heavy flowering and fruiting, very few mature shoots would be available at the time of fruit-bud differentiation or formation of floral buds and hence there would be little or no flowering next spring.
Manuring of the mango is, therefore, quite complex problem and a grower has to keep in view all factors involved in order to get good results.
The above doses are for the ‘off’ year of crop. During the ‘on’ year apply one additional kg of CAN or half kg urea in June. Apply the whole quantity of farmyard manure and phosphatic fertilizer in December. Apply all nitrogen and potash in February. During ‘on’ year, split the nitrogen dose into two parts, first part is given at the time of flowering and the remaining half in the month of June.
Ten tonnes of mango fruit produced in one hectare of land use 67 kg N, 16 kg P2O5 and 73 kg K2O.