Applenut,
Here are some links:
https://www.crfg.org/tidbits/gibberellic.html
@ILParadiseFarm started an experiment with this. He hasn’t yet reported back about the results and I’m hoping he will.
His post contains links to various articles about GA. You can find what he wrote at Gibberellic Acid 3 (GA-3) And Stonefruit Seeds.
Several sources sell GA through Amazon. One of them includes the following instructions in the product information section:
Dilute the GA3 powder; the GA3 powder is very hard to dissolve just by stirring in water alone. Proper dissolving can easily done by adding very small amounts of alcohol to the GA3 being used until the powder is dissolved (this very small amount of alcohol will not hurt your plants). The dissolved powder than can be added to the distilled water to produce the proper PPM dilution. (See chart below) Also recommended is the addition of a wetting agent; a few drops of agriculture soap can be used. It is very important to remember proper PPM dilution rates for success. Too much GA3 or too little can affect your end results. The GA3 needs to be applied in early morning before sunrise if possible. Bright sunlight will effect GA3, making it less effective or destroying its effect completely. Only mix what you’re going to use that day. The powder can spoil in high heat and will only last about one week once mixed. Wrap the unused powder container in aluminum foil to protect from direct sunlight. If stored in a cool, dry place, the powder can store for up to 2 years. Do not freeze or refrigerate. GA3 Powder 90% is soluble in 70% common rubbing alcohol. Before it can be used is must be turned into a liquid. The amount of Gibberellic acid that needs to be used is very small. Drop the correct amount of powder in a small bottle, then add a few drops of rubbing alcohol. The only reason to use alcohol is to dilute the Gibberellic acid powder. Use just enough alcohol to wet the gibberellic acid powder. If after a couple of minutes you can still see some powder, add a few more drops of alcohol. Then just add water to get the right concentration. It is often said that alcohol will damage plants, but not in the very low concentration needed to dissolve Gibberellic acid. 90% GA3 powder will not dissolve in water.
You’ll notice that it says “The GA3 needs to be applied in early morning before sunrise if possible.” The reason is that GA is not only useful for breaking the dormancy of seeds, it also apparently is a major growth accelerator for plants.
While the description of how to use GA is meant for people using it as a plant growth promoter, I’ve included it here because as you can see it needs to be handled and used in some fairly specific ways.
If you need to break dormancy for apple seeds and cooling is a problem, GA might very well be what you need.
BTW, how do you trick the apple trees into thinking they’ve gone through a winter chill period so they’ll bloom and produce without the winter chill actually having happened? Also, how does disease and insect pressure in the topics compare to typical North American conditions?