Know your Hydrangeas
Blue and white hydrangeas decorate long lunches and fill Church vases in the floral countdown to Christmas. Here we unwrap more goodies from the hydrangea family. You’ll think all your Christmases have come at once!
Words: Linda Ross
Blue-pink-purple flower heads depend for their colour on the pH of the soil. White flowers don’t have any pigment so won’t change colour. They prefer an easterly aspect for good morning sun and grow 1-3m. Prune lightly in autumn or winter. Plant with winter-flowering hellebores to distract from bare stems.
Dichroa febrifuga, syn D. versicolour
This unusual evergreen shrub belongs to the broad Hydrangea family and is great under trees, partnering lemon clivia, heuchera, plectranthus and cane-stemmed begonias. It’s native to mountainous Nepal, China and Vietnam and grows 2-3 m tall, with large toothed leaves, and blue or mauve, pH-dependant flowers massed in large rounded clusters. Prune after flowering and feed regularly.
Frequently seen in in Japanese art, these delicate-looking flower heads have showy sterile sepals around a central cluster of small, true flowers. Treat like mop heads.
The climbing hydrangea is one for cold climates and you may have seen it smothering the cool side of an English stone cottage. It’s deciduous and likes the cool shade of the south side of the house and regular water. Flowers, pure white and lacecap in form, pick well.
This is a standout shrub under trees, 1m x 1m, loved for its long flower panicles and scalloped, oak-like leaves which colour brilliantly in autumn. The flowers age into dusky pink, caramel and chocolate-russet tones and as a bonus these hydrangeas tolerate more sun than others and don’t require as much water. Look for ‘Snow Queen’ or the double ‘Snowflake’.
Hydrangea paniculata ‘Grandiflora’
Large panicles of flowers can reach a sensational 30cm long and cover the entire shrub, fading to pink as they age. This large, cold-tolerant shrub prefers full sun and is often used as a hedging screen. Prune lightly as soon as flowering is finished for even more flowers next summer. Look out for the pink form ‘Sundae Fraise’.
If your only complaint about hydrangeas is their once-a-year flowering, you’ll love the new non-stop variety. Adjust pH for deep-blue, pale-blue, deep-pink or pale-pink flowers or choose the new white ‘Endless Summer’. Treat like a mop top hydrangea and grow in morning sun with bucket loads of water.
Hydrangea arborescens ‘Annabelle’
This is a small bushy deciduous shrub, 1.2 x 1.2m, with large, rounded flower heads to 30cm across which start sage-green, turn white then turn back to green as they age. It will grow in sun or shade but must be given even more water in sun. It tolerates salt but not drought. Cut to the ground in winter.