Gibberillic Acid -3

I am no chemist, so I wouldn't be able to give a full description of GA-3,but I encountered it in N.C. Deno's  incomparable book: Seed Germination - Theory & Practice 2nd edition, where he discusses GA-3 and its effect on stimulating germination in many species. He says: " It is now proposed that gibberellins are natural stimulators of germination in certain species and that the evolution of this requirement is critical to the survival of those species."
 
As many species in Deno's study germinates much better with the use of GA-3, or in some cases is the only way to induce germination, I wanted to try this out for myself. I got to buy some GA-3 from another plant enthusiast here in Sweden, but later found it more easily obtainable from J.L. Hudson in La Honda, CA, or Gardens North, in ON. I would suggest anyone who would want to try the use of GA-3 to get Deno's book first.
 
This past spring I tried to germinate seeds of Salvia carduacea. Of 20 seeds sown in a sandy soil on March 29 none had germinated by May 6. I sowed another batch of 19 seeds in a paper envelope, and of these 1 germinated after 3 days. Many of you might have noticed that Salvia seeds get coated with a gel -like substance when they are placed in a moist environment. The germination takes place while this gel coat persisits, but eventually it dries out, and dis-appears,regardless of the moisture the seeds are subjected to, and then it seems like no more germination takes place.  . This happened to the remaining 18 seeds of S.carduacea after 18 days, with no additional germination.
 
I then treated the remaining 18 seeds with 500ppm GA-3 solution for 24 hrs, and within less than 24 hours after the treatment 7 of the 18 seeds had germinated. Three days after treatment a total of 12 seeds had germinted, and  after 5 days the germination count was up to 14 of 18. When the  experiment was stopped by May 17 one more seed had germinated, so after the treatment with GA-3 15 of 18 seeds germinated :(83 % )
 
The plants developed normally,and there was no obvious elongation in stem. According to Deno one has to experiment with concentrations of GA-3 to be able to get a natural balance, because GA-3 may cause elongation and other effects to certain species. 
 
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