It is a banner year for hydrangeas at Gibbs Gardens. Weather conditions have been favorable and the season is still going strong. There are over 1,000 blooms to see including both native and cultivated varieties. With the mild temperatures and spring rains, many hydrangeas are flowering about two weeks ahead of what is considered their normal bloom time.
I have always been charmed by the old-fashioned blue mophead hydrangeas and the many different variations. I especially like them in combination with common orange daylilies, sometimes called ditch lilies (maybe because they grow along roadsides and don’t require any special care). Bigleaf hydrangeas, Hydrangea macrophylla cultivars, thrive in high shade, with lots of light but protection from hot afternoon sun. Japanese maples and dogwoods provide the ideal canopy for theses hydrangeas. Shrubs like Anise, Illicium species, make good companions along with ferns and shade loving perennials. There are both mophead and lacecap varieties of bigleaf hydrangeas and the flowers can range from blue to pink to lavender. In acid soils (low pH) flowers tend to be blue. Pink flowers occur when the pH is higher, often when the plants are grown near limestone. White flowers don’t change colors.
A handsome native that is always popular (and with good reason) is the oakleaf hydrangea, Hydrangea quercifolia with oak-leaf shaped leaves and large white flowers, beginning in June or earlier, depending on the year. The blooms persist for weeks and often turn tinges of rose as they age. A real bonus is the cinnamon peeling bark in winter and the colorful autumn foliage in shades of red and burgundy. While oakleaf hydrangea is a predominant species that occurs throughout North Georgia, the cultivar ‘Snowflake,’ a selection with double flowers, is planted throughout the Gardens. Flowers on the oakleaf hydrangea occur on second year growth. You don’t have to worry about pruning unless plants get too large for the area where you have them planted. If space is limited, you may be better off with one of the dwarf cultivars like ‘Pee Wee’ or ‘Sikes Dwarf.’ Both of these selections typically reach heights of 2 to 4’ tall and wide compared to the species which can easily attain heights of 8 to 10’ tall.
Another native hydrangea with white blooms that occur on current season’s growth is the smooth hydrangea, Hydrangea arborescens, known to many for one of its selections ‘Annabelle.’ The flowers, anywhere from four to six inches across and up to twelve inches in diameter, remind me of lace. The Annabelles are one of the easiest hydrangeas to grow provided they receive adequate moisture and protection from full sun.
In addition to the hydrangeas blooming now in June, there are varieties that take center stage later in the summer including Hydrangea paniculata ‘Tardiva’ and Hydrangea paniculata “Vanilla Strawberry.’
Tips for Growing Hydrangeas