Everything you need to learn about cultivating apple organically. Learn about:- 1. Introduction to Apple 2. Climate and Soil Required for Apple Cultivation 3. Propagation and Rootstock 4. Planting, Spacing and Planting Density 5. Training, Pruning and Canopy Management 6. Nutrient Management 7. Orchard Management Practices 8. Harvesting Time and Yielding 9. Varieties.
Contents:
- Introduction to Apple
- Climate and Soil Required for Apple Cultivation
- Propagation and Rootstock of Apple
- Planting, Spacing and Planting Density of Apple
- Training, Pruning and Canopy Management of Apple
- Nutrient Management of Apple
- Orchard Management Practices of Apple
- Harvesting Time and Yielding of Apple
- Varieties of Apple
1. Introduction to Apple:
Apple (Malus pumila/domestica) an important temperate fruit of northwestern Himalayas and principal crop of Jammu and Kashmir, Himachal Pradesh, Uttarakhand and parts of Arunanchal Pradesh is cultivated in an area of 3,11,500 hectares and total production is around 19,15,400 tons (NHB 2012-2013). Jammu & Kashmir (J&K) state accounts for the maximum cultivated area followed by Himachal Pradesh, Uttarakhand and Arunanchal Pradesh. Recently its cultivation has also been extended to the states of Nagaland, Meghalaya, Manipur and Sikkim and Nilgiri hills in Tamil Nadu.
In Himachal Pradesh, Uttarakhand and Arunachal Pradesh the apple is grown as rainfed crop while in J & K apple is grown as an irrigated crop. The principal cultivated areas are Srinagar, Baramulla, Kupwara, Budgam and Pulwama in J & K, Shimla, Kullu, Kinnaur, Mandi and Chamba in H.P. and Nainital, Almora, Uttarkashi, Pauri, Tehri and Garhwal in Uttarakhand.
2. Climate and Soil Required for Apple Cultivation:
Successful apple cultivation requires frost free spring and ample sunshine during summer without wide fluctuations in temperature. The most apple varieties require 1000-1500 hours of chilling below 7°C during winter to break the rest period. These conditions are available at an elevation of 1500-2700 m above mean sea level in Himalayan ranges.
The average summer temperature should be around 21° to 24°C during active growth period. Low temperature, rains and cloudy weather during flowering period hamper bee activity, which affects cross- pollination adversely. The optimum temperature for fruit set is 21.1° to 26.7°C.
Well distributed rainfall of 100-125 cm during the entire growing season is a pre-requisite for optimal growth. Long drought spells and excessive rains during fruit development and foggy conditions at fruit maturity hamper fruit size and quality. Dry and cold areas in H.P. and J&K are most suitable for apple cultivation and production of quality fruits with attractive colour, high sugar content and longer shelf- life.
Loamy soils, rich in organic matter having a pH range of 5.5 to 6.5 with gentle slope, proper drainage and having good aeration are most suitable. However, flat soil areas are also suitable provided there is proper drainage to avoid incidence of collar rot, root rot and other soil-borne diseases.
3. Propagation and Rootstock of Apple:
Apple plantations are raised mostly on seedling rootstocks. Crab apple is most commonly used rootstock variety. Self-pollinating, varieties like Golden Delicious, McIntosh etc. are also used as rootstocks. Clonal rootstocks also have been recommended but have not been commercialized yet because of lack of infrastructure for mass multiplication.
Seedling Rootstocks:
Seeds of Crab apple or commercial cultivars are collected and are stratified by keeping seeds in moist sand either in open or in refrigerated conditions during December for 2-3 months at 2-5°C. At higher elevations, conventional method or direct sowing of seeds in the field is practiced. Stratified seeds are sown in seed beds at a distance of 7-10 cm in rows 30cm apart. After every four rows, 30-40 cm space is left to facilitate the cultural operations in the field.
The seed beds are covered with mulch to get better germination. One year old seedlings are ready for grafting/budding. For raising nurseries, only virus free mother trees should be used as bud wood source. The trees may be got indexed for the possible presence of virus by sending the twigs along with 10-15 leaves to the research laboratories for the virus confirmation.
Clonal Rootstocks:
Most common method for propagation of clonal rootstock of apple is by mound or stool layering. The clones are planted at 30cm distance in rows, 60cm apart. The mother plant is allowed to grow for one season to get established.
The plants are cut back to 3 cm from the ground level just before growth begins. When new growth is about 10 cm, the shoots are ringed at base and covered with soil leaving the growing parts exposed. Soil is then mounded at regular intervals until it is 30-45 cm high.
At the end of season, roots are formed at the base of the covered shoots. Rooted layers are separated, close to the ground level and these are planted on flat, deep and fertile soils, preferably with irrigation facilities. The promising clonal rootstocks suitable for Indian conditions are M4, M9, M7, MM 106, MM 111 and Merton 793.
The propagation methods followed are:
i. Chip budding in mid-June and mid- September
ii. Tongue grafting- February to March
iii. Cleft grafting- February to March (Top working method)
iv. T-budding in May and June
4. Planting, Spacing and Planting Density of Apple:
Planting is done from December to March. Early planting in December is desirable. In steep areas, planting should be done in the contour system or in existing terraces. The grafts may be planted in the middle of the terrace at appropriate spacing. In valley areas, planting systems like square or hexagonal can be adopted. As usual, pits are dug of size lm x lm x lm. In flat or valley areas, planting is done preferably in square system but in slopy areas contour or terrace planting is done.
Best planting time is in December- January months. While planting 25-30 kg well decomposed FYM/compost along with 2 kg vermicompost, 1 kg neem cake, 1 kg wood ash and 50 g each of Trichoderma viride and Pseudomonas fluorescens need to be added. Irrigation to newly planted saplings is necessary for getting a high survival rate.
While planting, the roots should be intact and properly spread in their natural position before covering with soil. The grafted plants should not be planted deeper than their natural position in the nursery. The graft union should be 25cm above ground level to avoid collar rot.
Normally in standard varieties grafted on seedlings or rootstocks are planted at a spacing of 6 to 7.5 m accommodating 180-250 plants/ha. The planting distance can be reduced according to vigour of rootstock. Dwarfing or semi dwarfing rootstocks should be used where the soils are flat, fertile and can be irrigated. High density planting orchards are precocious, easily manageable, have higher yield potential with superior fruit quality and higher returns/unit area.
Trials conducted in H.P. have shown that rootstocks M7 and MM 106 have been proved most useful in controlling size of the scion varieties of both standards as well as spur types. Thus a planting density of about 500 plants/ha in standard cultivars and of 1000 plants/ha in spur types can be adopted in areas which can sustain intensive cultivation in apple under conventional management.
Although organic orchards of apple variety “Pacific Gala” with high planting density of 1087 to 1553 plants/ha (with a spacing of 4.6m in between the rows and 1.4-2.0m between plants) using dwarfing rootstocks have been demonstrated in USA, but such high density even with semi-dwarf and dwarf rootstocks may not be feasible under Indian conditions.
This is mainly because of non-adoption of appropriate techniques in canopy management and also absence of precision in maintenance of intercrops in between the rows of plants. Considering Indian situations, wider spacing’s between two rows of plants even with dwarfing rootstocks is much more feasible.
The provision of additional space in between rows of apple plants under organic management has significance. As wide spacing will provide enough space for growing diverse crops like green manure/cover crops and short duration vegetables like peas and beans.
5. Training, Pruning and Canopy Management of Apple:
Training systems in apple are recommended according to type of scion variety. Training systems like modified central leader, spindle bush, pyramid and cordon are suggested. Modified central leader system of training has been found most appropriate for standard varieties grafted on seedling rootstocks. However, in intensive cultivation of apple where dwarfing rootstocks have been used, a spindle bush system has been found to be the best.
Moreover tree canopy management apart from size controlling rootstocks helps in containing the size of plants which further allows growing of intercrops successfully in between the tree rows. Canopy management comprises of removal of dead, broken, diseased wood, removal of crowding, parallel growing branches and water sprouts. Depending upon situations, at times even topping and side dressing may be required for opening the canopies.
6. Nutrient Management of Apple:
Pome fruits at yield levels of about 7-8 tons/ha remove approximately 100 kg N and 125 kg potassium, out of which nearly 77% of N can be returned back to the orchard in the form of leaves, flowers and thinned fruits, which can be ploughed back to the orchard soil directly. While in case of potash nearly 44% is permanently lost in the form of harvested fruits.
In case of calcium, although removal is almost comparable to N but over 95% is returned to the orchard soil through fallen leaves, flowers, fruits and pruning. This removal pattern is to be kept in mind while calculating the need for nutrient management from external sources.
As organic farming system relies more on feeding the soil rather than feeding the plant, thus in nutrient management major stress is laid on recycling of biomass, using open spaces for leguminous cover crops for green manuring and mulching, using liquid manure such as Jivamrit for hastening microbial process and compensating the shortfall with the use of vermicompost, concentrated manures and wood ash (or sulphate of potash in case ash is not available).
Nitrogen requirement at periodic intervals is fulfilled through repeated foliar applications of foliar feed solutions such as Vermiwash, Panchagavya or farm made protein hydrolysate.
(a) Feeding the Tree by Feeding Soil Life:
Organic apple orchards need a well-drained, moist and well aerated soil. Continuous moderate growth is the basic rule for fruit production and quality fruits. Soil life (bacteria, fungi, worms, etc.) provides good soil for growing fruits. They build a soil structure that drains if wet and sucks up water if dry. Soil life feeds on raw organic matter, root exudates, grass chippings, fallen leaves, prunings, animal manure and decaying weeds.
The humification part of soil life produces soil structure and humus. The mineralisation part of the soil life converts humus into easy up taken nutrients. Therefore entire biomass from fallen leaves, flowers, fruits, prunings, weeds and cover crops etc. need to be used as mulch and treated with Jivamrit. This needs to be done at least 3-4 times in a year during December, late February and May-June. Cover crops grown in interspaces need to be mowed down and incorporated in the soil.
(b) Using Cover Crops as Green Manure:
Clover (Trifolium sp) or any other suitable legume crop can be grown as green manure in the alleys or interspaces with very high seed rate. This will not allow any space for weeds to emerge. Once the crop is about 8-10 inches it should be incorporated in the soil. Nutritional requirements and control of pests and diseases of cover crops must be done in time.
(c) Compensating Shortfall by Organic Fertilization:
Considering the biomass recycled, and the nutrients being recycled, the short fall is calculated and applied as combination of various organic inputs. Normally if entire orchard biomass is recycled and at least two cycles of cover crop are used as green manure, only 40-50% of nitrogen and 60% of potash is to be replenished.
Under conventional management 10 year old plants are applied with 100 kg FYM besides 700 gm of nitrogen, 350 gm of phosphorus and 700 gm of potash and full quantity of FYM, phosphorus and potash are applied as basal soil application in December before snowfall. Nitrogen is applied in two split doses, first at 2-3 weeks before bud burst and second one month after flowering.
7. Other Orchard Management Practices of Apple:
Irrigation:
Most of the apple orchards in India are rainfed except in few districts of Kashmir valley. If irrigation facilities are available, irrigation can be given at 7-10 days intervals during critical summer months. For rest of the period irrigation can be given at 3-4 weeks interval.
In such areas having irrigation water source, drip irrigation needs to be adopted to cover more area under irrigation. The most critical water requirement in apple is from April to August, the peak requirement being after fruit set. During the entire growth period of apple it requires 15-20 irrigations.
Orchard Floor Management and Soil Moisture Conservation:
Weeds compete with apple plants for soil moisture and therefore tree basins need to be kept clean by hand weeding, mulching or black alkathene mulching. In cool climate black alkathene mulching is very effective in controlling weeds and conserving moisture, which ultimately improves fruit quality.
However, the use of black alkathene mulch should be avoided in wanner areas. Orchard floor management is accorded very high priority under organic systems as it controls weeds, conserves soil moisture and improves soil fertility. In countries of Europe and USA, methods like mulching, adopting Swiss-sandwich system for cover cropping and flaming are being used. Under Indian conditions growing cover crops in between the two rows of plants is best.
In the initial years of plantations, green manuring crops like clover and beans may be cultivated between the rows/ basins to improve soil texture and nutrient status. Hay or black polythene mulching immediately after spring rains can help to retain soil moisture. The nutrient needs and pest and disease management of cover crops must be looked into at the required time.
Fruit Drop:
Majority of commercial varieties of apple experience three phases of fruit drop, means early drop, June drop and pre-harvest drop. The early drop is considered natural and may occur due to lack of pollination and fruit competition. The June drop is caused by moisture stress and environmental conditions, which can be checked by, maintaining soil moisture through irrigation and mulching.
The pre-harvest drop has serious concern with the growers as the mature marketable fruits drop before harvesting due to physiological reasons. Application of Vermiwash @5 % at 15-20 days before harvest may be helpful in controlling fruit drop effectively.
Rejuvenation of Old Orchards:
Unproductive old apple trees need to be rejuvenated by heading back 3-4 main scaffolds to at least 15 cm during December-January months. Rest of the scaffolds are removed and cut ends are painted with Bordeaux paste. In May out of many shoots, select 1-2 outgoing in each stub. Rejuvenated trees need to be adequately looked after for nutrition and control of pests and diseases and they will start fruiting in third year.
8. Harvesting Time and Yielding of Apple:
Harvesting time varies with apple varieties and the location where it is grown. In Himachal Pradesh, peak harvest season is from August to September, whereas it is from July to September in Uttarakhand. However in Jammu & Kashmir, the peak harvest is from September to November.
At harvest the fruit should be picked gently and placed in picking bags. The fruits are transferred from picking bags directly to plastic crates, which are quickly shifted to pack house. Before shifting to pack house the fruits in crates are kept in shade to remove field heat.
Yield:
Yield in apple varies from state to state. Yield is highest in J&K state at 8.7 tons/ha. Apple yields are lower in H.P. and Uttarakhand at 3.9 and 3.7 tons/ha respectively. Yields are lowest in Arunachal Pradesh.
Post-Harvest Management:
Pack House Operations:
After receipt of fruits in the pack house, the fruits are dumped in dry dumper from where fruits are carried on a conveyor belt and sorting is done manually and washed in chlorine water using soft brushes. Thereafter the fruit is rinsed in clean water and extra water on fruits is removed by passing the fruit through absorbing rollers. Also if the fruits are to be sent to distant markets, the fruits are waxed using natural carnauva wax, Waxing is dried and size grading is done on packing lines.
Fruits are graded according to different grades keeping colour, size, shape and appearance into consideration. All these operations are done only when fruit is to be sent to distant markets or is to be exported; otherwise, the fruit is sorted manually in the pack house without using packing line facilities.
Then fruits are packed in CFB cartons usually having a net weight of 10.0 kg. After proper packing, CFB cartons are pre-cooled at a temperature of -1.1°C to 0.0°C and stored at this temperature with RH 85-90%. Most varieties can be stored for 4-8 months.
9. Varieties of Apple:
There is wide array of varieties of apple being cultivated in hilly states of India. Apple is a cross-pollinated crop and for good fruit set requires pollinizers.
Based upon various quality parameters, disease resistance and climate suitability following varieties are recommended under three categories:
Early varieties – Michael, Maayan, Mollies Delicious, Shlomit, Tydeman’s Early (P), Chaubattia Princess, Chaubattia Anupam, Early Shan Burry (P).
Mid-Season varieties – Cox Orange Pippin, Jonathan (P), Granny Smith (P), Red Delicious, Rich- a-Red, Red Chief, Royal Delicious, Golden Delicious, Well Spur, Oregon Spur, Red Spur, Gala, Lodh Delicious, Vance Delicious, Silver Spur, Skyline Supreme, Red Gold (P).
Late varieties – Top Red, Ambri, Lai Ambri, New Ambri, Vilayat Ambri, Yellow Newton (P), Sunhari, Fuji, Red Fuji and Golden Delicious (P).
Recently, improved Spur types and Standard colour mutants have been identified which produce trees of about 50-80% of the standard size with 15- 20% high yield potential, with early fruit maturity and better fruit colour.
The high yielding apple varieties namely Scarlet Gala and Red Fuji have also been introduced in HP and Uttarakhand. These varieties are being evaluated on size controlling clonal rootstocks M 9, M 26, M 7, MM 106 and MM 111. A number of scab resistant cultivars namely Prima, Priscilla, Sir Prize, Jonafree, Fiorina, Macfree, Nova Easy Grow, Coop 12, Coop 13 (Redfree), Nova Mac, Liberty and Freedom have also been introduced in J & K and HP.