A few years ago I started a cutting from a very pale blue lacecap hydrangea. When it flowered the first year it had pink blossoms so in the winter two years ago I applied aluminum sulphate at the advized rate and last summer had some blue-ish/pink-ish blooms. Last winter I doubled the application of aluminum sulphate (about 3 months apart) and the blooms are still coming out not pale blue (some are even pink). The original plant was in an almost uncultivated area with high amounts of fir and cedar needles in the soil...I assume the ph was very low....I haven't actually measured the pH of the container my plant is in..but assumed that the aluminum sulphate would have lowered it. The container is large and sheltered..must be hand watered in the winter..so that leaching out of the soil shouldn't be a problem...but I don't want to kill other plants in the same large container....Help...what am I doing wrong...I'd really like to get the sky blue colour back........Also have a hydrangea "endless summer" in the same container and it is blue.
It could be the water you are using. I've heard that before. Take a look here. Scroll down to color change. http://www.hydrangeashydrangeas.com/index.html Newt
Your soil might have a high buffering capacity. Soils high in clay or organic matter have a much harder time undergoing pH altering. My parents have two hydrangeas right next to each other, one is pink and one is blue, believe it or not. Okay this isn't trying to be grose or rude but it is totally true. My dad doesn't do anything different to the soil except when he works in the yard and needs a restroom break he "waters" the one hydrangea that remains blue. This may not have anything to do with it, but I think it is pretty funny and would throw that in there. He would be totally embarassed!!!
Hi Dixie, Actually ureic acid can be acid or alkaline. It depends on the person and what they eat. Newt
thanks newt. they have been planted back there for over 10 years so it has been "watered" many, many times.
