Gibberellic Acid will inhibit bloom but doesn’t work on all cultivars and I suspect would be even less effective in California
It works in Malaga for Osteen at least, 0.5 ml of gib. acid/per 1 liter, 3-4 times in Autumn every 15 days (how many times depending on hasl, coast plots needs just 3 applications, those in the hills need 4), starting when night temperatures drop below 15ºC (Sep-Oct). I'm trying it myself this year for the first time with some cvs (LZ, FP, NDM4, Keitt...).
Jose, do you know the final concentration of GA? I have the powder form so I will need the final concentration to know how much to dilute.
On a side note, I have been dealing with this issue for so many years and planting seeds from Polyembryonic varieties is one of the best solutions I can come up with so far. If you get lucky with a clone, you will get good fruit and not have to worry about flowering.
For those that don’t live in cold climates, the cold weather is one of the strongest bloom inducer that I know of. Here in SoCal, some of our Mangos are already blooming.
Once bloom occurs, much energy is wasted forming flower panicles and even if the panicles are removed, the tree will bloom again. The bloom at my location typically lasts 6-7 months. Half the year is wasted on a a fruitless effort. This is young trees I’m talking about. For fully mature trees, we want the blooms and fruit set but for young trees that are still establishing, this is a horrible thing to waste half the year.
We must remember that not only are we wasting time but the plant is wasting much energy as well. The bloom panicles are large and use up much of the stored resources. For a small plant, this can be 1-2 growth flushes of stored energy if it hadn’t bloomed.
Simon