can certain nutrients increase lilac’s fragrance?
I am getting 4-5 blooms the first of April in Oregon, which possess very minimal fragrance. Is there anything I can do to enhance that fragrance? What fertilizers would you recommend? I know ammonium sulfate is supposed to enhance blueberry size/flavor. Is there anything like that for lilacs?
My research did not yield any information to suggest it was possible to boost a lilac's fragrance through soil amendments. The potency of a lilac's fragrance largely depends on the variety (medium to dark purple ones are more fragrant) and can be influenced by the surrounding air temperature. I consider flower fragrancy to be more of a genetic disposition, the function of which is to attract insect pollinators.
Here is an interesting article that discusses the fragrancy of lilacs: