Three favorite summer-blooming beauties
Story and Photos by Troy B. Marden
June is hydrangea season in Tennessee. Sure, there are hydrangeas that begin flowering as early as May and continue through August and even September, but June is peak flowering time for my personal favorites and the time of year I enjoy them the most. I would be hard pressed to pick just one favorite, but I can easily narrow it down to three.
At the top of my list – my hands-down favorite every year – is Hydrangea quercifolia Snowflake (‘Brido’), the magnificent double-flowered form of our native oakleaf hydrangea. This is one of the largest growing cultivars of oakleaf hydrangea on the market, so site it accordingly. Give it plenty of elbow room and a few hours of strong morning to midday sun and it will reward you with 18-inch trusses of creamy white, fully double blooms for nearly three months every summer. As the flowers age, they will perform a spectacular color transformation, changing from creamy white to deep, reddish pink. Because the individual sterile flowers (the showy part!) continue to add new petals for several weeks, you will have deep pink (the oldest), green (middle-aged), and creamy white (youngest) petals all at once. This phenomenon occurs in each sterile flower, which combine to form a full truss of cascading pink, green, and white blooms. Can you tell I love it?
Tied for first place is another double-flowered form (and another native), but a different species, H. arborescens ‘Hayes Starburst’. This compact shrub will reach 3 feet tall by 4 feet wide in about five years. Beginning in mid-May, it opens its creamy white lacecap blooms ringed with sterile petals. As the flowers age, they begin to produce even more sterile petals, both around the edges and from the center of the inflorescence, eventually transforming from a single-flowered lacecap to a fully double mophead. It is best not to prune it other than to remove any dead wood once it begins to leaf out each spring. Light pruning to shape it is okay, but the most spectacular floral display will occur on old wood, so don’t prune too hard.
‘Hayes Starburst’ grows in one of the driest locations in my shade garden and gets about three hours of hot, direct sun at the end of the day with no ill effect. It never wilts and puts on a breathtaking show every summer. Be patient. It takes about three seasons to really hit its stride and during its early years, the blooms are often so heavy they lay on the ground by the time their cycle is finished. This is another reason for not pruning – to build up a good, woody structure to help support its blooms.
Finally, there is H. serrata ‘Blue Billow’, a fine blue lacecap that flowers almost every year without fail (unlike its more tender H. macrophylla cousins). Only the very coldest winters have ever knocked it back. It has flowered reliably eight of the past 10 years, while the traditional “macrophyllas” have flowered twice in the same number of seasons. In fact, I now have about six different varieties of H. serrata and will choose them every time.