Since pineapples flower erratically, induction of flowering is a common practice. This is done chemically by use of growth regulators which induces flowering and subsequent fruiting. Following growth regulators are recommended for different months to induce flowering.
Month |
Growth regulators & Concentration |
---|---|
September-January |
N AA 10 ppm ( PIanofix 1 ml/4.5 litres of water) |
March-May |
Ethrel 10 ppm (2.5 ml/100 litres of water) + 2% urea + 0.04% sodium carbonate |
All months |
Ethrel 25 ppm (6.5 ml/100 litres of water) + 2% urea + 0.04% sodium carbonate. |
The mixture is to be poured into the heart of the plant at 50ml per plant. If it rains within 24-36 hours after the application of the chemical the treatment should be repeated.
Pineapple cultivation in Vazhakkulam area became commercially viable after the introduction of the flower inducing chemical Ethephon in this area by the beginning of the 1980s. The pineapple crop is very responsive to the induction of flowering by plant growth regulators. This had made it possible for farmers to schedule the flowering of the plant and harvest to synchronise with the season of high demand and price.
For inducing uniform flowering at the desired period, apply 25 ppm ethephon (2-chloro ethyl phosphonic acid) in aqueous solution containing 2% urea and 0.04% calcium carbonate as follows:
The mixture (50 ml/plant) is to be applied pouring into the heart of 16-17 month old plants (39-42 leaf stage) during dry weather. For treating 1000 plants, 50 litres of the solution would be required. (The ingredients for preparing 50 litres of the aqueous solution are ethephon 1.25 ml, urea 1 kg and calcium carbonate 20 g, made up to 50 litres with water. The dosage has to be fixed depending on the availability of commercial formulation and the active ingredient contents). Flowering will commence from 40th day after application and complete on the 70th day.
Flowering starts by 30 days and completes within 40 days of growth regulator application. Fruits will be ready for harvest by 130-135 days after the application of growth regulator. Harvest over different months could be obtained by carefully phasing the planting and growth regulator application.
During summer months and festival seasons, there is heavy demand for fruit and the prices increase. Hence many farmers schedule the planting, growth regulator application and harvest to synchronize with the season of demand and high price.