How to do Commercial Plum Fruit?
Plum fruit is temperate in nature and is a major crop of the Hills, but in North Indian Plains, particularly in Punjab, it is a minor fruit crop but is of great importance.
The fruit is native to China but it became a commercial fruit of Japan and America and is also known as ‘Japanese Plum’ due to its cultivation in Japan and from there the cultivars were spread to other places.
At present, it is cultivated in all temperate climate countries of the world. In North India, high quality Plums are grown in the hilly areas of Himachal Pradesh, Jammu and Kashmir, Uttarakhand and Uttar Pradesh, and in the Plains, it is cultivated throughout Punjab, Haryana and in some parts of Uttar Pradesh and Rajasthan.
Some of the plantations of Plum are as Solid blocks that exist in Amritsar, Fazilka, Ambala and Kurukshetra. On an average, the Plum trees can yield upto 50-60 Kg of fruit.
We will learn more about its Cultivation in this article.
Introduction to Plum Fruit
Plum fruits or Prunus Salicina belongs to the family of Rosaceae and are popularly known as ‘Aalubukhara’ in India and they are hardy and productive and provide a bountiful harvest even on dwarf trees.
They are ‘stone fruits’ like peaches and apricots and are also known as ‘drupes’. They are very delightful fruit when they are fresh and are used in savoury recipes or baked into desserts. The fruits look very beautiful and their smell is also very good during the spring with pretty white and pink Blossoms.
The fruit requires low chilling and less juvenile period, so it is preferred for planting as a filler fruit plant as in Mango, Litchi, and Pear. The Plum trees are highly productive due to profuse flowering, high fruit set and early ripening of the cultivars recommended in the Plains.
The trees are medium in size, pruned to a height of 5-6 metres, else it can reach upto 12 metres height and 10 metres across. The bark of the twig and trunk of the tree is blackish brown in colour which is usually shredded from the old scaffolds.
The leaves are oblong in shape and are sharply pointed. The leaf margins are serrated with green colored lamina above and light green colour on the lower surface. The tree usually flowers in the first fortnight of February.
The flowers are bronze on small spurs with very close rings and they occur closely and inflorescence is termed as ‘cymose’.
The fruit is a drupe or stone having thin edible exocarp and fleshy mesocarp and the hard stony endocarp contains seed. The fruit is rich in Sugar and Vitamin A and it is eaten fresh or processed into jam and squash.
Health Benefits of Plum
The health benefits are mentioned below:
- Plums have high content of Vitamin C and are known to be good Antioxidants.
- They have unique phytonutrients called neochlorogenic and chlorogenic acid.
- It is rich in vitamin A,B, Thiamin, Riboflavin and Minerals like Iron, Phosphorus and Calcium.
- It helps in the production and absorption of Iron in the body leading to better blood circulation.
- It has anticancer agents.
- It reduces the chances of contracting a heart disease in the long run.
- Dried Plums are called ‘prunes’ and they have a great Ayurvedic medicinal value which is helpful in curing jaundice and summer bite.
Commercial Varieties of Plum
There are tons of Plum varieties and are typically categorised by European, Japanese, Hybrid and American types with each variety having their own benefits.
The commercial Plum varieties grown in India belong to the Japanese group and their fruits have the best taste and are suitable as fresh fruit while the other cultivars are used for processing.
The important Plum varieties cultivated in India for Plains require a low cooling period. The different Plum varieties are listed below:
- Kala Amritsari – They are medium sized fruits with round and dark brown colour. The fruit flesh is yellow & juicy, suitable for jam making and they ripen during mid May with an average expected yield of 45 to 50 kg per tree.
- Satluj Purple – This variety has a large size and bright crimson colour with thick flesh and has excellent shipping quality. They ripen in the second week of May with an expected yield of 30 kg per tree. This variety is also planted with Kala Amritsari to improve the yield as it is self incompatible.
- Jamuni Meeruti – They are small sized & yellow coloured fruit with thin skin and have a soft melting flesh. They ripen during the end of April with an expected yield of 28 kg per tree.
- Titron – This variety are medium sized fruits with thin skin and deep Purple colour. It has yellow coloured flesh and is good for jam making. They ripen in the second week of May and their expected yield is around 25 to 30 kg per tree.
- Kataru Chak – It is a self fruitful variety and the yield can be improved when pollinated with Kala Amritsari. They are large in size with purple colour and creamy flesh.
- Aloo Bukhara – It is a self unfruitful variety and is planted in rows alternating with those of Howe. They are large sized fruit with yellow colour and sometimes it is tinted with red. The pulp is juicy and sweet and is usually served as a fresh fruit.
- Howe – This variety is large sized with round shape and sweet & juicy. They turn red during the maturity period and ripen in the second fortnight of May with a yield of around 30 to 35 kg per tree. The yield of this variety can be improved with Aloo Bukhara as a pollinizer.
- Alpha – These varieties are round in shape and small in size with red colour during the time of maturity and they ripen in the second week of June with a yield of 25 kg per tree.
- Late Yellow – These are round shape and medium sized, juicy and sweet fruit. They are lemon yellow coloured during the time of maturity and they ripen at the first fortnight of May with an average yield of 25 kg per tree.
- Alachua Black – This variety is small in size with dark purple colour. They ripe late in the season. They are planted with ‘Titron’ to improve the yield.
- Peshawari Kala – This variety yields less but they have very good quality fruit which are black in colour and have thick skin.
- Damson Plum – This variety is a medium sized fruit with round shape and thick yellow skin and is juicy. They ripen in the first week of June with an expected yield of around 40 kg per tree.
Climatic Requirement for Plum Fruit
Plum proposes a temperate type of climate and is generally found growing from higher Hills in Srinagar to Jaipur in Rajasthan and in some areas around Delhi. It requires less chilling hours of a temperature below 7.2 degree Celsius and it can even tolerate Frost and high summers.
Therefore, it can be cultivated in low temperature of upto 20 °C and highest at 47 °C and some cultivars like Santa Rosa can be cultivated in higher hills with 700 to 1000 hours of chilling and some cultivars require a low chilling period of about 250 to 300 h which are preferred for plains.
Plum performs well in soil that has high pH values of 5.0 to 6.5 and therefore it is preferred as a filler over peach.
The sand should be well drained and Sandy loam to medium loam soils are mostly preferred for the soil and it should be deep in nature with a good water drainage and it should be free from saline and alkaline conditions. The trees thrive well in neutral soils.
Propagation and Root stock in Plum fruit
Plums can be propagated through cuttings and through seed. Usually they are propagated through hardwood cuttings. Kala Amritsari is propagated through hardwood cuttings and the cuttings of Kabul Green Gage is also used for grafting other Plum cultivars.
The rooted cuttings are used directly without budding and the planting distance recommended for Plum cultivation is 15 by 30 cm. For raising the Rootstocks like Peach, the Plum seeds are sown in November and they germinate in Spring season and the seedlings are allowed to grow single stemmed.
The seedlings are made of pencil thickness and are budded during May to June season. Generally, T-budding or Shield is preferred for good results. The remaining seedlings can be grafted during December to January.
Plums can be propagated successfully on wild Apricot, Peach and Plum rootstocks and the Peach rootstock is generally recommended for light soils.
Plantation in Plum Fruit
Plums can be transplanted in the main field during the winter season after the scion has grown for 1 year with a spacing of 6 m by 6 m in rows and plant with square system method accommodating about 275 Plum trees per hectare.
Training and Pruning in Plum fruit
The Plum plants should be trained according to the Open Centre depending upon their growing habit. Some Japanese group varieties have a spreading habit and they are better adapted to open centres of training whereas some varieties with an upright growing habit should be trained to a modified system.
The leader branches should be modified after 4 years of planting and 4 to 5 well spaced secondary branches should be obtained.
The Plum trees bear fruit after one year old wood and spurs on older wood. Light pruning is recommended to bear trees in January month and for encouraging new growth and healthy spurs.
Manure and Fertilizers in Plum fruit
The fertilisers and manures depend on the type of soil and the age of the plant. The Sandy soils require more fertilizer than heavy soil types.
In general, 60 kg of urea, 30 gram Nitrogen and 6 kg Farmyard Manure, 95 g of superphosphate, 15 grams of P2O5 and 60 g of Potash with 36 g of K2O per year age of the tree is beneficial for meeting the nutrient requirement of Plums and after 6 years, the fertilizer dose should be increased to 36 kg of farmyard manure, 360 g of Urea, 570 g of super phosphate and 375 g of potash and the same dose must be repeated subsequently.
Phosphorus and Potassium and Farmyard manure should be applied during the month of December. In Spring, half of Nitrogen should be applied before flowering period and the rest half after 1 month and if the soil have a deficiency of Zinc, then this should be corrected by foliar spraying of 3 kg of Zinc sulphate along with 1.5 kg of unslaked lime mixed in 500 litres of water.
Intercropping in Plum fruit
Some leguminous crops like black gram, green gram, cluster beans and pea can be cultivated with Plum as intercrops during the non bearing fruit period of the plants.
Fruit thinning in Plum Fruit
The thinning of the fruit should be done by hand before the pit hardening stage and the fruits should be spaced 5 to 8 cm apart.
Weed control in Plum fruit
For controlling the weeds in Plum plants, weedicides should be used. Diuron with Terbacil @ 3 kg per ha or 4 kg per ha or Simazine @ 4 kg per hectare is recommended during the pre-emergence period and for post emergence period, Glyphosate @ 800 ml per hectare or Gramoxone @ 2 litre per hectare is recommended.
Irrigation in Plum fruit
The plants should be given sufficient water during the months of March to May, depending upon the variety used for new growth, flowering and fruiting. In the subtropical areas, the Plum plantation requires highest water during April to May month which coincides with the excessive fruit development period. To get more yield you can use drip irrigation method for quality fruit and more yield.
Pest and Diseases in Plum fruit
Some of the Western diseases in Plum plants are:
Crown Gall, Bacterial Canker, Powdery mildew, Plum Curculio, Black Knot, Brown Rot, Plum borer, Leaf roller, Cherry fruit fly, Rose Chafer, Japanese beetle, Thrips, Scab and some birds.
These can be controlled by clearing away the infected part and keeping your tree well watered and ensuring that the nematodes are under control.
You can even use several types of fungicides to control them. You can use Neem Oil which is useful both as a pesticide and a fungicide.
You need to inspect your trees regularly and remove infected branches and you can even contact your local Horticulture department for understanding the disease or infection and getting a proper solution for it.
Harvesting in Plum fruit
Plums are very perishable and so they should be packed with very good care. The optimum maturity standard varies with the variety of fruit and their use and if the fruits are planned for local consumption, they should be allowed to mature on the trees.
All the Plum fruits do not ripe at the same time, so they should be harvested in several pickings. The foods can be collected in small baskets padded with rice trash or grass at the bottom and sides and they are covered with paper and tied in gunny cloth.
The fruits are then graded before packing in baskets or wooden boxes. The fruit is born on Spurs, so they should be taken care to save the Spurs from breakage during their Western period.
For distant markets, the fruits should be picked when they are firm and have developed 50% colour on the skin and the fruits should be harvested along with pedicels to avoid any injury to the fruit.
Yield of Plum
The yielding depends on the variety of fruit cultivated and the farm management practices. On an average, you can expect a yield of about 40 kg per tree.