Everything you need to know about pomegranate cultivation! Learn about: 1. Botany of Pomegranate 2. Origin of Pomegranate 3. Soil and Climate 4. Orchard Cultural Practices 5. Propagation Techniques 6. Planting Operation 7. Manuring and Fertilization 8. Crop Regulation 9. Flowering and Fruiting 10. Training and Pruning 11. Harvesting and Handling 12. Varieties.
Botany of Pomegranate:
The genus Punica has two species viz. granatum and protopunica. Punica protopunica is found wild in Socotra Island and Punica granatum is cultivated in tropical and subtropical parts. Punica granatum has been classified into 2 subspecies i.e. cholorocarpa and porphyrocarpa. Chorocarpa is found in Transcaucasus region and porphyrocarpa in Central Asia.
i. Punica Granatum:
It is a deciduous shrub or tree upto 6.5 m in height and relatively long lived (upto 50-70 years). Leaves are petioled, oblong or oval-lanceolate, 2.5-5 cm or long lengthwise, obtuse, glabrous and shinning. The handsome brilliant orange red flowers are axillary, solitary or in small clusters and borne towards the ends of the branchlets.
The calyx is tubular, persistent, five to ten-lobed, the petals five to seven in numbers, are lanceolate, inserted between the calyx lobes. The ovary is embedded in the calyx-tube and contains several locules in two series one above the other. The fruit is berry and edible portion is fleshy testa of seeds.
ii. Punica Nana L:
It is also called as Dwarf pomegranate. It seldom grows higher than a man and usually treated as a pot plant in the North. It is the best kind for green house use. The double flowered habit is more common. It is as hardy as granatum species and is suitable for outdoor work where the climate is not too severe. On the pacific coast it is grown as a hedge plant.
Origin of Pomegranate:
The pomegranate is an ancient and important fruit. It is symbolic of plenty and a basket of pomegranates was chosen as a symbol of the 18th International Horticultural Congress. It is a popular fruit and according to latest figures constitutes over 20 per cent of the fresh fruits imported in India. Pomegranate, Punica granatum, belongs to the smallest botanical family, Puniaceae.
Pomegranate is a native of middle-east (Iran and adjoining countries). In India, maximum area is found in Maharashtra particularly in the districts of Ahmednagar, Pune and Wardha etc. Other important states growing pomegranate are Gujarat (Dholka), Rajasthan, Karnataka and Tamil Nadu and to a limited extent in U.P It grows all over India, but thrives best in places with a hot dry summer, provided irrigation is available. In humid weather, the quality of fruit is not good.
It can stand considerable frost and grows up to an altitude of 1600 metres. A wild type called ‘Daru’ grows abundantly in the lower Himalayas. Its fruit is not edible, but the dried seeds give an important condiment called ‘anardana’.
Soil and Climate Required for Pomegranate Cultivation:
The edible part of the pomegranate is the juicy outgrowth of the seed called the aril. The sour arils of the wild type, when dried along with the seed, give the ‘anar dana’ its flavour. Where the winter is cold, the tree is deciduous, but in the plains of India it is evergreen. It can tolerate alkaline and wet soils.
Many pomegranate plantations in India have been raised from seedlings as in the case of guava, but the seedlings vary too much. Propagation from hard wood cuttings is easy. Cuttings of 20 to 25 cm length from fully mature i.e. one to two year old shoots are taken. For improved rooting a quick dip of 20 seconds in 5000 ppm. Indole Butyric Acid (IBA) solution is beneficial. These cuttings are planted on raised seed beds leaving only one or two buds above the soil. Layering is also possible.
In general a spacing of 3.5 to 5 metres in poor soils of Deccan and 5×5 metres in light and deep soils of Maharashtra and Gujarat is recommitted. In Rahuri (Maharashtra) for higher yield in initial 4-5 years of planting a distance of 5 m x 2 m is adopted. Alternate rows are removed afterwards to maintain a planting distance of 5 m x 4 m.
The fruits are borne terminally on short spurs arising from mature shoots. These bear fruit for three to four years. Only a limited pruning of the bearing tree is, therefore, required. The gradual growth of new shoots should be encouraged by restricted cutting back of the bearing shoots. Suckers are removed regularly.
Pomegranate flowers in spring in North India, but in Central and South India it flowers almost throughout the year. However, the flowers are most profuse early in the monsoon season. The spring flowering (Ambe bahar) gives fruits in summer, when the demand is maximum.
However, the fruit quality is poor. Flowering is, therefore, artificially induced early in the rainy season, as in the case of citrus. For this purpose, the roots are exposed in April and manuring and irrigation are done in May. After this treatment, the fruits ripen in November-December.
There are many types of pomegranate, including the double-flowering, ornamental type and a white-flowered type. The latter has a very poor fruit quality. In the cultivated types, the sugar content varies from 12 to 16 per cent and the acidity from 1.5 to 2.5 per cent. Dholka is the important variety of Gujarat. It has white flesh and soft seeds.
In the Poona area, the variety Alandi or Vadki, with deep pink flesh and hard seeds is important. A selection from this variety with soft seeds is Ganeshkhind No. 1. This has now been named Ganesh, an introduced variety, Paper Shell, with soft seeds and pink flesh has been found successful in South India. Bedana and Kandhari have been reported satisfactory from Himachal Pradesh.
Orchard Cultural Practices for Cultivating Pomegranate:
i. Irrigation:
The newly set plants require regular irrigation so that the roots become well established and the plants can start growth. The plants may be individually watered daily or about a week after planting. In northern India where planting is done during the spring, regular watering may be given every 7 to 10 days till the start of the monsoon. In areas where planting is done during the monsoon, irrigation may be given whenever there is no rain for a prolonged period of time.
After the plants are well established, in about 6 months, they can stand considerable amount of drought and irrigation may be given at intervals of 2 to 4 weeks depending upon the soil, climate, weather conditions and intercrops grown. However, during summer irrigate the plants at an interval of 10-15 day.
Regular irrigation is essential from flowering to ripening of fruits, as irregular moisture condition results in dropping of flowers and small fruits. It may also cause development of cracks on mature fruits which reduces market value and consumer acceptance.
ii. Intercropping:
Intercropping in pomegranate orchard is highly desirable because it takes about 6-7 years to come to commercial bearing. Vegetables viz. cabbage, cauliflower, tomato, radish, cucurbits, moong, peas, beans or green manure crops can easily be followed in pomegranate orchard.
The growing of intercrops should be carried out for the first four years of the life of the plantation. It is usually advisable to allow the intercrops to grow throughout the year. Intercrops can be continued for another 3 to 4 years after the plants had started bearing. It is best to grow a green manure crop during the monsoon and burry in it, when it has completed its vegetative phase and started flowering.
iii. Manuring and Fertilization:
In northern India, farmyard manure is applied during December. Nitrogen should be given in two split doses, first half should be added in February and other half in April. In other areas, manuring may be done just before the start of monsoon in case of young plants.
The one year old tree should be manured with about 5-6 kg of farmyard manure and 20 g nitrogen. This amount is increased by the same amount every year so that a five year old tree gets 25-30 kg of farmyard manure and 100 g of nitrogen.
At Mahatma Phule Krishi Vidyapeeth, Rahuri, an application of 500 g N, 125 g P2O5 and 125 g K2O is recommended for ‘Ganesh’ variety. Under Udaipur conditions of Rajasthan, application of 240 g N, 160 g P2O5 and 60 g K2O per plant is suggested for variety ‘Jodhpur Red’. In Gujarat state pomegranate is applied with 50 kg farmyard manure, 500 g N, 250 g P2O5 and 500 g K2O per plant per year. Application of fertilizers is done in December-January for Ambe bahar, in May-June of Mrig bahar and in October-November for Hasth bahar.
In Andhra Pradesh, adult bearing trees are applied with 800 g N, 400 g P2O5 and 400 g K2O per tree along with 100 kg FYM per tree. In Karnataka a dose of 200 kg N, 300 kg P2O5 and 100 kg K2O along with 12.5 tonnes per hectare farmyard manure is applied.
In Orissa, 45 kg N, 115 kg P2O5 per hectare along with 10 kg FYM + 100 g sterameal per tree are applied. In Tamil Nadu, 600 g N, 500 g P2O5 and 1200 g K2O along with 30 kg FYM is incorporated per tree per year.
Propagation Techniques for Pomegranate:
Pomegranate plants raised from seed vary widely and are undesirable. Thus, they must be raised vegetatively. Among the vegetative methods of propagation, cuttings are universally used for raising pomegranate plants on commercial basis.
Mature wood is used for making the cuttings and these are 8 to 10 cm long. The cuttings are planted in the nursery fields in such a way that not more than one-third of the cutting is exposed. The best time of making the cuttings is December-January when the plants shed leaves.
The cuttings made during September-October can also root satisfactorily. The cuttings in the nursery fields are planted directly after making them from the plants. For getting high percentage of rooting dip cuttings in 100 ppm IBA for 24 hours before planting in nursery beds.
Pomegranate may also be propagated by air-layering or gootee. Treatment with 10000 ppm Indole Butyric acid in lanolin as carrier was found to improve rooting. Ground layering is another method used for multiplying the pomegranate plants.
Planting Operation for Growing Pomegranate:
Land is prepared thoroughly and levelled prior to pit digging. The layout is done following square or hexagonal system. The size of the pit should be 60 x 60 x 60 cm. Pits should be filled with 22-25 kg of farmyard manure or compost, 1 kg of superphosphate and good soil mixture.
The plants are planted at the distance of 6m x 6m apart in square system and it will accommodate 275 plants per hectare. In higher but deeper soil, the planting distance can be reduced to 5 x 5 m.
Planting density is the most important yield contributing factor which can be manipulated to attain the maximum production per unit area. The optimum spacing is important for the maximum utilization of land and good income over a long period. At MPAU, Rauhari, it was observed that as the plant density was increased, yield per hectare also increased without affecting fruit quality. A density of 1000 plants per hectare gave 2-3 times higher yield and 2.44 times more profit as compared with normal plant population of 400 per hectare.
It was also recommended that for higher yields for the first four to five years after planting, a distance of 5 x 2 m may be adopted and alternate plants may be removed after wards maintaining a planting distance of 5 x 4 m. The cultivar Ganesh can be planted at the distance of 3 x 3 m and Kandhari at 4 x 4 m apart.
The best time of planting pomegranate in northern India is dormant period i.e. January to mid-February and in South India during monsoon season.
Manuring and Fertilization in Pomegranate Trees:
A basal dose of 20-25 kg FYM per plant at the onset of monsoon should be given. A fertilizer dose of 600 to 700 g N and 200 to 250 g each of P and K per tree/per year is recommended for fully grown trees. The time of application depends on bahar treatment followed. The yield in different parts varies from 50 to 200 fruits per tree.
The treatment of pomegranate fruits with Waxol + Carbendazim (0.1%) improves the storage life. Pomegranate Cv. Ganesh can be stored for 3 weeks at 25°C and for 10 weeks at 8°C with film wrapping. Heating the arils of pomegranate fruit at 40°C has been found to improve juice yield improves its T.S.S and its anthocyanin pigments in Cv. Ganesh.
The most serious problem of pomegranate cultivation in India is the splitting or cracking of fruit. Sometimes more than 50 per cent of the fruits are cracked. It is due to the hardening of skin of the fruits during periods of shortage of moisture and then sudden expansion of the inner part of the fruit after rain or heavy irrigation. The fruits are often harvested prematurely to avoid fruit-cracking, but the fruit quality is very poor in this case. No cure of the trouble is known so far.
The trouble can be minimised by improving the water retention capacity of the soil by adding organic manure to it and by regular and light irrigation throughout the fruiting season. The varieties like Guleshan and Bedana are reported to be resistant to fruit cracking. Spray of GA (120 ppm) in the month of June is useful. Spray of anti-transpirants like pinolene (5%), liquid paraffin as vapour guard, four to five weeks before harvest minimises fruit cracking.
Some people add powdered bricks to the soil with the belief that it would improve colour of fruit and flesh. There is no more justification for this than in the practice of adding milk to the roots of mango to make it sweet and creamy. However, this practice probably reduces fruit-cracking by improving the moisture-retaining capacity of the soil.
Another menace to its cultivation is the attack of the anar butterfly (Virochola isocrates) which bores the fruit. The affected fruits develop a rot. Spraying carbaryl (0.2%) or Metacid 50 EC (0.1%) or Phosphamidon (0.3%) at fortnightly intervals is effective to control the pest. First spray is done on developing fruits when only one or two fruits are seen to be infested.
Another pest found in India is the bark eating caterpillar. The caterpillar bores the back and feeds inside. The affected portion should be cleaned by removing all webs and cotton soaked in kerosene or petrol should be inserted into the holes and sealed with mud. Treatment with carbaryl (1%) is also effective.
Crop Regulation:
The pomegranate starts fruiting in about 4 years after planting and continues for about 25 to 30 years. Economic yield is generally obtained after 10 years of planting.
To regulate flowering, water is withheld for about two months in advance of the normal flowering season. After two months, manures and fertilizers are applied and light irrigation is given. Three to four days later, heavier irrigations at normal interval are followed. The tree readily responds to this treatment by producing new growth and blooms and bears a good crop.
A full grown pomegranate has tendency to bear flowers and fruits throughout the year. To obtain higher fruit yield during a particular period, plants are given a resting period by which the natural tendency of the tree is altered with artificial means. It is done by withholding of water for about 2 months in advance of normal flowering, root exposure and also use of chemicals.
By adopting such methods flowering can be induced in June-July (Mrig bahar) coinciding with the break of monsoon, February-March (Ambe bahar) and September-October (Hasth bahar). These practices are known as bahar treatment.
Mrig bahar is taken in Deccan areas where water is so scarce during the hot weather. The flowering, therefore, is so forced that the maximum requirement of water-falls during the rainy season. For this treatment, watering is withheld from December to April-May results in sufficient suppression of growth.
In the month of March-April leaves are shed as plants go to dormant stage. The manures and fertilizers are applied and the light irrigation is given which is followed by two heavy irrigations at 7 days interval before rain set in. Within 15 days, trees will put on profuse growth along with the formation of flowers and fruits. The fruits ripen in October and continues upto December.
Ambe bahar is taken in the areas where enough water is available during hot weather. The fruits are available during June and July and no irrigation is given after the start of the rainy season. The trees shed their leaves by October-November, when a shallow hand digging or ploughing is done.
During December-January, manures are applied. The first irrigation is given in January and the flowers appear within a month of this irrigation. In dry regions of western Maharashtra Ambe bahar has been found to be better treatment than Mrig bahar.
Hasth bahar is seldom taken. The trees have to be made dormant during August-September. This is rather uncertain because of the rains that occur during this period.
Pollination:
Both self and cross pollination are recorded in pomegranate. Greater percentage of fruit set was observed by hand pollination and pollination under natural conditions i.e. open pollination.
Flowering and Fruiting of Pomegranate:
In evergreen pomegranate cultivars, the flower buds of the spring flush are borne on mature wood of one-year old shoot, whereas the flowers which appear during July-August are borne on the current year’s growth. In deciduous cultivars, the flowers are borne on the current year’s growth between July and August. The flowers are found mostly in clusters, either terminally or in axils of the leaves. The inflorescence is cyme and due to heavy drops of secondary and tertiary buds they appear to be solitary in clusters.
In Western India, three flowering seasons i.e., Ambe Bahar (January – February), Mrig Bahar (June – July) and Hasth Bahar (September – October) have been reported. Ambe Bahar is most commonly favoured by the growers because of high yield consequent to profuse flowering. In Punjab, only one flowering season is observed from April to June. In Bihar, flowering occurs twice, once during February – March and again during July – August. In Karnataka, flowering was observed in July – August, March and September.
The flowering period extended for 80 to 87 days in first flowering and 22 to 30 days in second and third flowering. The flowering period of different cultivars is also quite variable. Under Delhi conditions, Dholka, Kandhari, Muskat and Patiala flowered only once in a year while Ganesh and Japanese Dwarf flowered twice. Heterostyly is common in pomegranate flowers.
The time of dehiscence of anther varied in different cultivars and no general sequence was found in the time of anthesis. Anthesis in Punjab started at 8 AM and was complete by 4 PM with a peak at 2 PM. The stigma was receptive one day before anthesia and remained receptive for upto 5 days. The percentage of pollen grains that germinated was over 90 in most of the 21 cultivars studied. After open pollination, fruit set was highest in cultivar Dholka (63.8%), Bedana, (63.0%) and Kali Shirin (62.7%).
After self-pollination, fruit set was appreciably lower. Fruit development was determined at fortnightly intervals between 18 April and 8 August. On 8th August, the cultivars Kazki, Shirin Anar and Achikdana had the largest fruits, 6.50, 6.32 and 6.26 cms in diameter, respectively. Fruit cracking was lowest in the cultivars Kazki, Guleshah and Bedana.
Training and Pruning of Pomegranate:
Training:
Pomegranate may be trained as multi-stemmed tree or single stemmed tree.
(i) Multi-Stemmed Tree:
In this method 3-4 stems are left at hill and remaining shoots are removed, this will give a bush from look to the resultant tree. In Maharashtra, the growers prefer multi-stem training by retaining all stems. But yield has not been found to be affected by number of stems per plant.
(ii) Single-Stemmed Tree:
The single stem up to 30 cm is left by removing all the side shoots at the time of planting. The main stem is headed back at a height of about one metre results in the formation of branches. Four or five well distributed branches on all sides above 60-70 cm from the ground level are allowed to grow. In the third year of planting one can maintain desired shape of the pomegranate. Single stemmed tree has tendency to produce less number of shoots.
Pruning:
Pomegranate does not usually require pruning except for removal of suckers, dead and diseased branches and developing a sound framework of the tree. It is essential to remove the suckers as soon as they arise. The fruits are borne terminally on short spurs produced all along the slow growing mature wood.
These bear fruits for 3 to 4 years. Therefore, only a limited pruning of bearing tree is required. Annual pruning in winter during dormant period should be confined to shortening of the previous season’s growth to encourage fruiting.
For getting a good crop, a set of new shoots should be allowed to develop every year on all sides of the tree and gradual growth of new shoots should be encouraged by restricted cutting back of the bearing shoot.
Harvesting and Handling of Pomegranate:
Pomegranate is a non-climacteric fruit. Its fruits become ready for harvesting in 5-7 months after the appearance of blossoms. Mature fruits become slightly yellowish and further pink to red. On tapping, the fruits give metallic sound and when pressed they give a ‘Crunch’ sound. The fruits are harvested with the help of secateurs.
The period of fruit harvest is November to March in Mrig bahar, June to August in Ambe bahar and February to May in Hasth bahar. The corresponding flowering period is June to August in Mrig bahar, January to February in Ambe bahar and October to November in Hasth bahar.
The trees begin to bear fruit in the fourth year when a small crop of 20-25 fruits (4-5 kg) per tree may be harvested. In the 10th year, it rises to 100-150 fruits (20-25 kg). The average yield in well managed plantation may be as much as 200-250 fruits per tree.
After harvesting, sorting of fruits should be exercised to remove undesirable fruits. The fruits should be properly graded before packing to fetch higher premium in the market. The fruits are graded in to 5 grades viz. A, B, C, D, E grades. A grade fruit should have minimum 400 g weight and 90 mm in diameter.
The fruit weight and diameter should be 350 g – 80 mm in B grade, 300 g – 70 mm in C grade, 250 g – 60 mm in C grade and 200 g – 50 mm in C grade. The fruits should preferably be packed in CFB cartoon of 4 – 5 kg capacity.
Export specifications are variable for different countries. Ganesh and Bhagwa varieties are exported to Middle East having 300 – 350 g weight of red coloured fruits and to Netherlands/ Germany and UK having 250 – 300 g weight of red coloured fruits. Arakala and Mridula varieties are exported to Middle East, Netherlands/Germany and UK having 200 – 250 g weight and deep red fruits. The fruits are packed in 3 – 5 kg capacity boxes and sent at 5°C temperature.
The healthy fruits are packed mostly in bamboo baskets and wooden crates containing 10-12 kg with padding of paddy straw or dry grasses. The fruits can be transported to distant market without any loss.
The fruits can be stored for about 5-6 months at 4.5°C and 80- 85% relative humidity. The shelf life of wax treated and intact film wrapped fruits of cv. Ganesh could be extended upto 6 weeks at 4 – 5°C and upto 4 weeks at ambient temperature (26 – 27°C). The storage life of pomegranate fruits in sealed polythene bags (0.02 mm) at 10°C is extended upto 12 weeks.
Varieties of Pomegranate:
Different cultivars have been recommended for the commercial cultivation in different states in India on the basis of physico-chemical characteristics. In north India, there are no well recognized commercial varieties.
Brief characters of important cultivars are given below:
1. Ganesh:
It is an improved variety known as GBG No. 1. Ganesh is a seedling selection by Dr. G.S. Cheema at Pune. It is a selection from Alandi and considered to be the best variety. The fruit is medium in size. It has soft seeds. Ganesh is a high yielding variety and is a good cropper. The flesh is pinkish and has juice with agreeable taste. Its main crop (ambe bahar) in North India matures in mid-August. TSS of Juice is 13 per cent with low acidity (0.5%). The average yield is 15-18 tonnes per hectare.
2. Alandi:
Fruit medium in size, fleshy testa, blood red or deep pink with sweet slightly acidic juice. Seeds are very hard. The variety is named after the name of the village where it was grown extensively.
3. Dholka:
Fruit is large in size, rind greenish white, fleshy testa, pinkish white or whitish with sweet juice. Seeds are soft. Juice is acidic. It is medium cropper. It is an important variety of Gujarat.
4. Kandhari:
It produces large fruit. The rind is deep red. The flesh is dark red or deep pink. The juice is slightly acidic. The seeds are hard. The variety is successfully grown in Himachal Pradesh. The juice is sweet with 12 per cent TSS and well blended with acidity (0.61%). It is regular bearer variety and yield 10 – 13 tonnes fruit per hectare.
5. Muskat:
This variety is also largely grown. Fruits are small to medium in size. Rind is somewhat thick. Fleshy taste, with moderately sweet juice. The seeds are rosy in colour. Fruits are tasty.
6. Nabha:
Tree is medium in growth, fruit skin yellowish and smooth. Cracking medium Juice is 65 per cent. The arils are light pink in colour. Seeds are medium soft. Taste is good.
7. Jalore Seedless:
It is soft seeded variety of Rajasthan. The fruits are large in size with average weight 200 g. Fruits are attractive in appearance with pink to deep red skin. The arils are pink to red having soft seeds.
8. Mridula:
It is a soft seeded hybrid with excellent fruit quality. The arils are blood red in colour with TSS 17.8 per cent and acidity 0.47 per cent.
9. Bassein Seedless:
It is soft seeded red coloured variety grown in Karnataka. The average weight of fruit is 327 g. The arils are light pink in colour with TSS 15.6 per cent and acidity 0.49 per cent.
10. Jyothi:
It is variety with soft seeds and pink aril has been released from University of Agricultural Sciences, Bangalore. This is a selection from the seedlings of Bassein Seedless and Dholka varieties. The average fruit weight is 219 g. Its TSS is 15.0 per cent and acidity 0.58 per cent.
11. PAU Selection:
It originated as a chance seedling from Ganesh. Plants are vigorous and evergreen. Fruits medium to large, weight 450 g. Aril’s are white transparent with little pink tinge but seeds are little hard. The juice percentage is 71, TSS 13 per cent and acidity 0.7 per cent. The average yield is 8 tonnes per hectare.
12. Bhagwa:
The tree is medium in size, bushy, partially deciduous. The fruits are medium to large in size, rind smooth, glossy, red in colour with soft seeds having red coloured aril. The fruit weight is 215 g, juice 45 per cent, TSS 14.2 per cent and acidity 0.48 per cent. The average yield is 14.6 kg per plant. The main crop matures between mid-August to mid-September.
Some other varieties of pomegranate are:
1. G-137- It is a clonal selection of Ganesh with better fruit size, aril colour, T.S.S. and high juice (88%) content.
2. Yeracud-1- From Tamil Nadu have medium size fruits, easily peel able rind, soft seeds and attractive deep purple aril.
3. Mridula- A hybrid of Gulsha Rose Pink x Ganesh developed at Rahuri has fruits with deep coloured aril along with soft seeds and high T.S.S.
4. Jallore Seedless is a known cultivar of Rajasthan and Gujarat.
5. Ruby from I.I.H.R., Bangalore is a cross between a deciduous cultivar of deep red aril colour and sweet with evergreen type. It has dark red non sticky and bold aril, soft seeds, very sweet and low in tannin content.
6. Amlidana is another hybrid (Ganesh x Nana) from I.I.H.R., Bangalore. It is superior to sour variety Daru. Its fruit provide more acidic (16%) anar dana, higher yield, short stature and suitable for high density planting.