This time of year I am amazed to see spectacular mounds of Hydrangea 'Annabelle' glowing around the metro area. That is one cultivar that has certainly made its mark, although one doesn't see quite as many of them as you would in a more humid part of the country. I've noticed a few other sorts here and there--including small plants of the blue species (I think the jury is still out on these when it comes to our climate however.). There is one particularly striking hydrangea that has really proven its mettle for many, many years at Denver Botanic Gardens. The Oakleaf Hydrangea (according to the USDA) is restricted to just the eight southeastern-most states, and yet the plants shown above have persisted in a dense stand of English Ivy alongside Denver Botanic Gardens' Waring House for nearly 30 years.
Blossoms of the typical wild form
The common wild form has long, graceful flowers that form a bit of a cone shape up to a foot long. Like others in the genus, the fresh flowers are white, but age a lovely soft green. If you cut them and hang them in a cool dry spot, they can make wonderful dry flowers for the winter too!
Hydrangea quercifolia 'Snowflake'
Growing alongside the typical form is a more compact flowered and smaller leaved cultivar that looks a bit more like the Eurasian species. It seems to have fared just as well over the decades, and makes for a nice contrast. All forms of this wonderful shrub turn glorious orange and pink in the fall, reminiscent of their native cousin Jamesia americana, that grows everywhere in our mountains (the only member of the family that does).
Both cultivars together
Here you can see both cultivars growing alongside one another more clearly. Surely, if they can grow well in this most challenging spot, nearly swamped with thirsty ivy, imagine what it might do in a well prepared spot in your garden with some compost and TLC? We have another handful of cultivars of this wonderful plant elsewhere on our grounds--but not enough! Come to think of it, I have a perfect spot in my garden for one... I better go out and get it before you beat me to the punch!