What is your best deep purple Macrophylla Hydrangea?
Mine so far is 'New Wine'.
I think it is only sold as a florist plant but the one I got made a great shrub here in the Seattle area z8b.
With lime it also makes a stunning red (see group photos). But I have other great reds and an am taking it back to the harder to achieve purple color.
The 'Mathlida Gutges' multicolor in the group photo was shifted by lime in the compost I used at the new location and so I'm shifting that one back to the electric colbalt blue I had before. I have a second one that will be that great multicolor.