Hallo Vijay,

I think the quality of your water is your number one priority. I image you need to irrigate a lot in your climate and the chlorine in your water will have a very negative influence on the biological life in your soil and lead to a build up of salts in the soil which will cause real problems for your plants. If you can afford an RO unit that will be fantastic and an investment I am sure you will not regret.

0,52% organic matter will improve through the addition of compost and through healthy plants, and by following the 5 principles for soil health. Be careful where you get your compost – it should be well balance and free of pollutants and salts. Well composted animal manure can contain a lot of Phosphorus. Zinc, Boron and particularly Iron can be supplied short term with foliar applications. You will want to encourage biomass/organic matter production with adequate irrigation so water is really priority number one!

I have no experience with tropical soils, but I understand that the nutrition is more in the plants than in the soil. You have the optimal condition for lots of growth – if you have enough water (and your soil can not hold very much at the moment) – so water is again number one!

What kind of soil do you have? Sandy?