I am a master gardener and love, love, love helping people with their flowers...
I am a master gardener and love, love, love helping people with their flowers and gardens. With every one of their questions, I learn more. I have a friend in Watertown whose niece planted 3 hydrangeas 2 years ago with blue flowers. I don’t know the name of the cultivar. I was amazed when she told me that the shrubs are still blooming blue flowers. She says that there has been blue spruce trees next to two of the shrubs on the north that dropped their needles etc. in that area for many years and the one shrub on the south where a spruce had been removed and the shrub is now planted. Could that soil have become acidic enough to produce the acid for the flowers? Or, has a hydrangea been developed to produce blue flowers? Neither of my ideas seem likely to me but then I really don’t know. I’d really like an answer to my quandary. I’m excited to find the why of of the blue flowers. Will you help?
Clark County South Dakota
I’m sorry. I believe I did not make myself clear. I’m wondering why my friends hydrangeas have blue flowers. The soil in SD is not acidic enough to produce blue flowers yr after yr. on hydrangeas.
Sorry, I took that as the soil was being amended to get the hydrangea blue but if that is not the case, it is surprising that they would remain blue for so long as a majority of cultivars color is predetermined by the soil acidity. I've searched and haven't found anything other than what we already know (I cant find anything on a blue cultivar that won't just change back to pink when plopped in our soil). The needles from pines will make the soil acidic to some extent but that is temporary (and limited to just at the surface) as the needles break down, and after a few years the acidity returns to 'normal'. I'm also just a MG, and hydrangea aren't my thing, maybe Dr. Ball knows more
Thank u for your response. We r of the same mind when it comes to blue flowers. I’m glad to know that the spruce needles could make the top soil acidic. I just couldn’t believe that the acid could change the soil and on both sides of the house at that. But then, I certainly don’t know much when it comes to the wide wonders of this earth.
I will continue to investigate. Maybe next year the flowers will be pink and the mystery will be solved.
Thank u for your help. Tika