Hydrangeas have been popular garden shrubs going back to olden days. They are cherished for consistent performance and easy care. In summer, we anticipate the beautiful, large and long-lasting blooms of hydrangeas.
However sometimes hydrangeas DO NOT BLOOM! We despair! How do we solve this mystery?
To begin, many of us have test-planted “Easter” or “Florist “ hydrangeas after receiving them as gifts. They have beautiful, big blooms in pink or blue. Often grown in greenhouse conditions: they lack cold hardiness. They are commonly named: mophead, bigleaf, lacecap or easter hydrangea. (H. macrophylla)
All plants need time to establish root systems, especially a struggling florist hydrangea. After one or two years when established, energy goes to blooms.
During harsh winter conditions, unprotected mophead canes die back to the ground. Because they bloom on “Old Wood” all the buds are lost!
In this area, winter and spring 2014/2015 had harsh freeze/thaw conditions that resulted in extensive bud “kill”. With ten hydrangea shrubs, my garden had only one bloom. This single oakleaf hydrangea bloom appeared at soil level, saved by snow cover. Happily the spring of 2016 saw a return of profuse flowering.
Over-fertilizing with too much nitrogen creates leaves only. Phosphorus is needed to encourage blooms. Use a balanced or slow release fertilizer sparingly.
Locate hydrangeas away from winter winds, with morning sun and afternoon shade. Too much sun or shade inhibits blooms.
Consistent moisture is needed. Wet soil rots their roots. They fail in extended drought.
And finally, PRUNING may be the answer to our mystery!
Sometimes we mistakenly prune the buds off! So resist the temptation to prune off those unsightly canes in fall cleanup. They may have next year’s buds!
Hydrangeas are popular because they demand little attention! They will grow and bloom freely without pruning. Pruning is only needed to eliminate damaged, diseased, dead and crossed branches in order to support healthy growth.
There are two types of hydrangeas. Ones where the blooms grow on “Old Wood” and ones that grow on “New Wood/Growth”. Pruning care is different for these groups. If you wish to tidy your plant refer to the species list below:
Blooms on “Old Wood”:
Early summer to midsummer. Prune right after flowering just below the flower head. Do not cut canes back.
H. macrophylla: (Mophead, Lacecap, Bigleaf, Easter). Rounded shape- pink and blue.
H. quercifolia: (Oakleaf ): Conical shape opens white, fades to pink, brown. Leaves like oak leaf.
Blooms on “New Wood/Growth:
Midsummer to frost. Can be cut back in winter, early spring to ground or to new bud.
H. paniculata: (Hardy H., Pee Gee, PG). Conical shape opens to white, turns pink.
H. arborescens: (Annabelle, Smooth, Snowball). Ball shape opens green, turns white and then green.
(Note: New “everblooming” hydrangeas are now available. They have both old and new wood to allow for endless blooming. Treat them as an “Old Wood” variety to be safe. )
Happy Hydrangeas!
Susan Mason