Ruby Slippers Oakleaf HydrangeaRuby Slippers Oakleaf Hydrangea for Sale Ruby Slippers Hydrangea (Hydrangea quercifolia) is a dwarf oakleaf hydrangea native to North America. The proper planting time is early to midsummer, as this fast growing plant produces a cluster of 9 inch, white, conical blooms that quickly age to deep pink by fall. Similarly, the dark green, deeply lobed foliage turns reddish brown as it matures while the leaves stay strong and lively, even after heavy rain.