HelpfulGardener.com

Hello.

I love Hydrangeas and have planted a few in my landscaping recently. I am new to growing them and not sure about the way color change works. I know some change colors based on soil pH, but do all except for the white ones? I am wondering if I can expect this with the three kinds I purchased as they were all marketed as being a specific color.

The three kinds I have are:
- Next Generation Pistachio (macrophylla)
- Endless Summer Bloomstruck (macrophylla)
- Invinvibelle Ruby (arborescens)

Thanks,
Roxanne

Yes, the white ones do not change color based on soil pH. But, sometimes, they have "a button" that grows in the center and it sometimes turns blue-pink based on soil pH. Also, some blooms of white hydrangeas can turn blush colors instead of their normal white. Not sure what is up with that but it is very rare and not all years. I have noticed this in my Mme. Emile Moulliere blooms now and then. Oh, last thing, immature blooms of white hydrangeas sometimes open yellowish but the yellow goes away quickly, in a week or less.

I think you will really like your Pistachio!

Thanks, Luis. But do you know if the three kinds I have change color based on soul pH? I actually don't have any white ones, just the three listed.

Only the macrophyllas change color based on soil pH. So the first two you mentioned should do that. The H. arborescens probably not. For blue flowering macrophyllas, aluminum in the soil is even more important than acidity.

I do not know about Ruby. The previous "pink Annabelles" that were on the market were a shade of pink different but you had to put them together to notice.

Pistachio may have a little color change per Proven Winners but it is a nice shrub. Low spreading and compact. Good for pots/containers. It has nice lateral growth at the base, mostly clusters of spires or something resembling spires. Maybe that is why is called for a castle: Schloss Wackerbarth in Europe. The stems look to be sturdat and rigis. The leaves are small, cupped, a bit thick, red tinged around the edge. Some people have noticed that it is not winter hardy (prev year's stems die off) but it blooms on basal growth and new growth.

Bloomstruck is supposed to be more ph sensitive and is supposed to produce blooms of various shades of color. However, if your soil pH is very acidic or very alkaline, the effect will not be as dramatic. I asked about that and was told that it would probably display many shades of all pink or many shades of all blue when the soil pH is high or low.