What has been fascinating about this for  me is noticing the differences in vigor, disease resistance and  flowering is very consistant from nursery to nursery. So even with the  variables of soil, fertilizer, irrigation and hardiness zones, certain  cultivars always outperform the others. This is not just true for  Hydrangeas- I see this in Camellias, Hostas, Roses and all of the other  species we favor with wide cultivar selections.
Of the  Hydrangeas, there is one cultivar that has been terribly overlooked by  gardeners and landscape designers. I think that it never took hold  because consumers have come to associate Hydrangeas with blue,  volleyball-sized mopheads. 'Lady in Red' does not satisfy that  description. 
Introduced by Dr. Michael Dirr from the  Department of Horticulture at the University of Georgia, Hydrangea  macrophylla 'Lady in Red' has many qualities that make it unique  and superior to many Hydrangeas on the market.
DISEASE  RESISTANCE: Most Hydrangeas are susceptible to Powdery Mildew and leaf  spots caused by Colletotrichum and Cercospora. These  diseases not only impact the aesthetics of the plants, but also the  overall vigor. Plants that become infected with these diseases tend to  lose their leaves earlier in the season and have reduced flower size  (over time). 
'Lady in Red' is resistant to Powdery  Mildew. If a 'Lady in Red' Hydrangea is growing in the center of a group  of Powdery Mildew-laden Hydrangeas (let's say 'Claudie' which is one of  the worst), it will not get diseased. The same holds true for the leaf  spots.
The foliage alone is reason to  grow this plant. 
FORM: The stems, which are a  gorgeous wine-red, are sturdy and upright. This plant does not flop and  fall apart like some of the traditional mopheads. The flowers are  smaller, so they do not pull the stems down to the ground.

That  being said, understand that 'Lady in Red' does not have the LARGE  flowers like a blue mophead. And I just know that this is the  reason it did not become the blockbuster that 'Endless Summer' has  become. We are not a nation of subtleties.
USE IN THE  LANDSCAPE: 'Lady in Red' should not be planted alone. This plant is  going to be most effective when planted en masse. Trust me on  this. Just looking at this pictures taken at a North Carolina nursery  (Fair View Nursery) and you see what I mean. You really want five or ten to  really make an impact.

I could see this plant growing in front of a thick evergreen screen or planted near the foundation of a grey or stone building. Plant a large sweep of Black-eyed Susans or 'Autumn Joy' Sedum in front of the 'Lady in Red' Hydrangeas and I think it would be really impressive.
It is time to re-examine this cultivar.
I think it is a shame that it is not used more in the industry because it has all of the qualities we tell breeders we want: compactness, multi-season interest, flower, disease resistance. Fact is, if it wasn't a Hydrangea, we would all be using it. We've just got an image in our heads of what a Hydrangea is supposed to look like.....and 'Lady in Red' doesn't fit that image.
Love, love, love this plant. And you should, too.
