Yes its the hormones that are mostly attributed to the growth boosts.
there is some confusion, the foliar sprays should not be a substitute for regular soil fertilizers.
most benefit would come at the time of flowering, and at fruit set.
while looking around for Avocado tests, i did come across many others, in Citrus, the size, and taste of the fruit remained the same, but production increased using foliar sprays. but one added benefit, was that fruits matures up to 7 days ahead of time, which was considered beneficial to those trying to get better market price.
http://www.google.com.do/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CDkQFjAB&url=http%3A%2F%2Fwww.fshs.org%2FProceedings%2FPassword%2520Protected%2F1994%2520Vol.%2520107%2F82-85%2520(KOO).pdf&ei=qT7wUJP1L4-08ATk0IFA&usg=AFQjCNEDJgSWAOEmkHI8hxPy5vrDVhF2YQ&sig2=Z9HdGqNmZkeTvtvCLaNrDw&bvm=bv.1357700187,d.eWU&cad=rjaRegarding the azomite, or rock dust, I believe its a matter of availability, just spreading it on the surface, around the trunk of a tree, may not be enough, if its not leaching down and making contact with the roots. I do not see rock dust being very effective in, non organic systems and would take time so that those minerals are in a form that can be picked up by the roots.
On the other hand, foliar spray of trace minerals or other nutrients, are available in just hours to the plant.
For some crops the boron in seaweed may not be enough, Avocado from my understanding has heavy requirements, and so does Papaya. yes seaweeds have all these minerals, but seaweed alone may not have the amounts of certain minerals to get the maximum benefit in them, seaweed may have boron , iron, zinc, and cobalt, but the question is, how much does your crop need, and will the application of seaweed supply all that is needed?
Seems no matter where seaweed was used, the results were some kind of benefit, reduced insect problems, less fungal problems, almost always an increase in production, and in many cases better tasting product and increased size, tomatoes, lettuce, mangoes, herbs, potatoes, and so on. lots of research has been done on this.
And its so damn cheap, the stuff is so concentrated, that the dry powder stuff you buy needs to be diluted like 3000-5000 to 1, and your only doing maybe 2-3 sprays a year.
I was very interested in the benefits of the yeast in combination with the seaweed. how amino acids, and vitamins in the yeast also increased plant yield and brix at least in mango. another product that is cheap, and easy to get.
In an earlier post I mentioned Cobalt, i have come across a few articles on the results of cobalt applications in mango. this study also include choline.
http://www.google.com.do/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CC4QFjAA&url=http%3A%2F%2Fwww.lifesciencesite.com%2Flsj%2Flife0801%2F40_4621life0801_337_343.pdf&ei=sTzwUOWAPJSm8QTeroGgBw&usg=AFQjCNH64M7y726elyqF3l1iA_gANAWOAg&sig2=oYIb_oNFQDNBqIwxUjYWtQ&bvm=bv.1357700187,d.eWU&cad=rjaAnyway, the original question was about rock dust and minerals to increase fruit size, I think that if conditions are good in the soil, the rock dust does wonders, and studies have shown, that certain minerals applied to the leaves of some crops can indeed increase their size. seaweed and rock dusts are just 2 forms of getting trace minerals to your plant. seaweed has many other benefits in addition to just the trace minerals.
anyway all my posts on this matter, may lead some to think I represent some seaweed harvesters organization lol. all i wanted to share was that I have come across many and I mean many studies on this, and they seem unanimous in the benefits of seaweed, and if you noticed I try to avoid studies made by companies pushing any particular product. or testimonials from people that have used the product. as that is not very scientific. I could apply seaweed to my plants this year but climate may have been bad, so I may think that the product had no added benefit. controls are needed under the same condition. and also, the controls should be fertilized the same as the test plants, minus the product under test. I wish I had the room to do these tests for myself. someday I will.
