TAKING APPLE CULTIVATION TO TROPICS

Apple is basically a fruit of colder regions of the world and so in horticulture it is categorized as a “temperate fruit”.  It is believed to have originated in or around Kazakhstan and hence Almaty, the capital city of Kazakhstan is called as fatherland of apples.

 With time, the popularity of this fruit increased and its cultivation of spread to all the temperate regions of the world.  Soon, on account of various reasons, apple became number one fruit of the temperate regions. 

         Gradually, people in lesser cold regions, also became interested in growing apples in their areas.  So efforts began among the horticultural researchers to extend apple cultivation to less cold regions.  Consequently, low chilling varieties of apple like Rome Beauty, Vered, Anna, Dorsett Golden etc. were developed.  These varieties can grow at those places where the winter is less intense and of short duration too.  But “some” winter is must for them and without that their trees will not have normal growth and flowering after the winter season was over.

         In the mean time during the past 60-70 years, another development also took place.  Some fruit enthusiasts in tropical countries also tried to grow apples in their home gardens, possibly for fun sake or to have a tree or two of apples in their fruit collections.  At some of these places, this fruit, which was so far known to grow only in cold regions, also started growing and fruiting successfully. These were the areas which had no winter season at all and where the minimum temperature never fell below 12 ° C during any part of the year and where the summers were also not very harsh. 

         One of such areas was Batu in Indonesia which is situated almost at the Equator.  This area, which is a district in Java island of Indonesia, has now acquired the reputation of apple producing region where you see red as well as green coloured apples being sold at all the village as well as roadside fruit shops.  And this happens all the year round as every month of the year is apple season in Batu.  You see apples orchards where apples and bananas are growing together at the same place.  This is a sight I would not have otherwise believed had I not  seen it four years ago with my own eyes during my visit to that area. 

         Apple growers of Batu take two crops in year just like the grape farmers in some parts of South India.  The most amazing part is that these people have “tamed” their apple trees in such a manner that they harvest their crop at time that suits them according to the market conditions.  It is virtually “defiance” of nature.

I had gone there on social visit to one of my ex-students who works there  for an Indonesian mushroom producing company at Malang.  In fact, I had gone on a short vacation to Bali and had taken this trip from Denpasar.  My stay at Malang was very short, only for five days.  But I got very much interested in this “horticultural wonder” and talked to the local farmers and tried to understand that how this all was happening.  I also started thinking on the possibilities of repeating it in some parts of South India where there is no winter season.

         I was told that the apple cultivation in that area was started nineteen fifties and the mooter of this revolutionary idea was one Mr. J. Krieben, who was an “electrician” by profession with no formal training in fruit growing.

 Apple fruits in a Batu orchard

Apple and banana growing together at Batu, Indonesia

An apple tree at Tumkur, Karnataka.

Apple fruits at Somwarpet, karanataka.  The picture was taken on Jauray 30, 2014 1nd this tree was planted on January 2012.

        

HOW DOES IT HAPPEN

Like other deciduous plants, apple tree also grows in phases.  There are two phases of growth, active when the plant flowers and bears fruits, and dormant, when it sheds its leaves and stays dormant and apparently inactive for a few months.  The dormant phase has probably created by nature to protect the trees from the winter injury.

 

         The two cycles have been wonderfully designed by the nature and are controlled by complex hormone controlled physiological processes taking place within the trees unnoticed by us.  As the winter season starts approaching, production of a set of hormones begins within the plant which initiates changes in the plant body leading to leaf fall and then dormancy which desensitizes the tree towards low temperature thus protecting it from the possible low temperature injuries.  As the days pass, the winter sets in.  Then the winter chilling triggers the production of another set of hormones in the plant body which start neutralizing the effects of the first set of dormancy inducing hormones and the tree wakes up again and resumes its normal activities of the spring and the following summer season.  This cycle continues throughout the life of apple but all other deciduous trees too. 

         Now if the tree (when young), at the end of winter season, is removed from its place and then planted at a place where the outside temperatures are favourable for its growth, it will sprout to activity and will start growing.  Now if this “new place” is such where the outside environment is conducive for vegetative growth, without any break during any part of the year, which is a normal feature of tropical climate, this apple tree will get “confused” and keep growing incessantly throughout the year without any break.  As there is no winter or “prewinter” like season so the formation dormancy inducing hormones within the plant body will not be initiated.  Therefore it will not become dormant.  As there is “no dormancy,” so there will be “no need” for any winter chilling to break the dormancy.  In fact this tree will turn “evergreen” like all other trees at its new habitat. 

         It may also be noted that the “chilling requirement” of the variety will also not matter at this place.  It will not make any difference in their growth whether the apple varieties are “high chilling” or “low chilling”.  Once the chilling requirement has been met at the place of their origin (nursery), there will be no further need for chilling.

         That is how it happened at Batu and the few other similar places.  The trees were taken from nurseries in apple areas at the end of winter season.  They had already met their annual chilling requirement at the nursery site at that time.  So when planted at the new place, they started growing and as there was no winter season to retard or stop their growth, so they just kept growing and growing incessantly.

MY EXPERIENCE IN INDIA

After seeing apples being successfully cultivated at a warm place like Batu, idea struck my mind that if this could be achieved in India, it might revolutionize apple orcharding there.  In many parts of South India, there are areas which do not experience any winter and the temperatures there do not fall below 12°C during winter months and therefore chance of trees entering dormancy were not there.  In India, apples are grown only in the hills of North India and this area is not enough to meet the requirement of apples of the whole country.  Secondly, the average annual apple production in India currently was 6.5 tons/ha.  This could easily be doubled by taking two crops in a year.

         So I wrote letters to some people and also got an article published in a Kannada language farming magazine, telling them about the possibilities of apple growing in some parts of Karnataka state.  Many people evinced interest and later at my suggestion formed a small group under the leadership of Mr. Krishna Shetty, an ex-banker turned farmer at Mangalore.  In January, 2011, I sent Mr. Shetty a bundle of 300 apple plants of assorted self-fruitful cultivars raised on seedling rootstock.  Mr. Shetty distributed these plants to 19 farmers from different locations in Karnataka State of India.  We started waiting for the outcome, particularly the performance of these trees after October when winter usually starts in India.  We got feedback from many places that the trees had not shed their leaves and kept growing incessantly like other trees.

          Then came the report that at some places, the trees had even flowered in the second year of their orchard life which was very unusual, rather unheard, as these plants are raised on seedling rootstock which take 5-6 years in India to put forth first flowers.  Some trees had even set the fruits.  Then in March 2013, I received e-mail containing pictures of a tree at Tumkur, 70 km from Bangalore, which had attained a height of 12 feet in just two years and was also bearing fruits.  

         This was very exciting news for me.  It indicated that the idea had worked and there were bright possibilities of apple cultivation in tropical India on the lines of Batu.  So I also decided to visit the places and observe the trees personally.  I had never gone there before.  I spent five days from 20 to 24 April, 2011 and visited several places between Mangalore to Bangalore, had a look at some of the trees planted in and after January 2011, and reached at the conclusion that it was possible to grow apple trees, irrespective of their chilling requirement, in warmer tropics provided:

• ·        these are planted at their new site in 2-3 days.

• ·        the “new site” has no winter season and the temperature there does not fall below 12 C in any part of the year.

• ·        the summer is also not too harsh to affect the growth of apple plants adversely.  The temperature should ideally remain below 40 C.

WHAT ELSE IS EXPECTED TO HAPPEN?

1.   The vegetative growth will be much faster and the trees may attain a much larger size than is usually under normal apple areas.  So it will have to be taken care of.  Spur type varieties or plants propagated on dwarfing rootstocks may offer a solution.

2.   New plant protection problems may arise and a suitable solution will have to be found for them.

3.   As the apple trees will now be growing under new conditions with a changed behavior (deciduous to evergreen), so the earlier production technology of temperate zone will not be applicable.  Depending upon their behavior in the new environment, a new package of cultivation practices will have to be developed.

It may take a decade or even more for standardizing the whole process but it is possible to do it.  A padre from France had experimented like this with grapes in tropical Southern West India 200 years ago.  And now, we have a large grape producing area with the highest production of grapes in the world. Wine companies from France have now come there for sourcing locally produced wine and then sell it under their brand names.