GARDENER'S READING ROOM
The Art of Gardening
Trees and Shrubs

Hydrangeas

If roses are the royalty of the summer garden, hydrangeas are at least their top courtiers. In fact, they could very well instigate a coup. What other plant blooms for most of the summer? Comes as a shrub, a vine, or a tree? Is relatively disease and pest free? AND provides both fresh and dried flowers? Hydrangeas provide all this and more!

Hydrangeas include over twenty species and subspecies - in fact, whole books have been written on the genus. (Van Gelderen and Van Gelderen’s
Encyclopedia of Hydrangeas is an excellent one.) At Sky you’ll find three broad groups: tree-like, shrubs, and climbers.

H. arborescens 'Annabelle'

H. paniculata

The tree-like group consists of the species Hydrangea aspera, H. arborescens, H. paniculata (peegee), and H. quercifolia (oakleaf). These plants prefer sun and well drained soil. H. aspera has traditional lacecap flowers in blue or pink. H. arborescens can have white ball type flower(‘Annabelle’ and ‘White Dome’) or lacecap (‘Villosa’). The oakleaf and peegee hydrangeas offer lilac-shaped white inflorescences that blush pink with age. Many of these hydrangeas are grown to resemble a small tree with trunk and branches. They can also be grown as a multi-stemmed tree, getting 6-10’ tall and wide.

The climbing group is the smallest, consisting of three species: Hydrangea anomala petiolaris, H. integrifolia, and H. seemanii. All climb by clinging and have white lacecap flowers and shredding bark. They do well against a wall or lattice; they can even be formed into a hedge. Both H. integrifolia and H. seemanii are evergreen.

H. macrophylla

The shrub group has one species, Hydrangea macrophylla, but hundreds of different varieties. This is the species most people visualize when they think “hydrangea”. These deciduous shrubs range in size from 2’ to over 6’. They can have either a ball-type flower or a lacecap, and flower colors can range from pure white to electric or powder blue, pink or red, even purples and mauves, depending on soil chemistry. You can change your hydrangea bush’s flower color from year to year by playing with this chemistry. Generally, you acidify soil with aluminum sulfate to intensify blues, and you raise soil pH with potassium nitrate to get richer pinks and reds. Most blue varieties can turn to red or pink, but not all red varieties can turn blue. Sometimes a plant will give varying color flowers all at once!

H. quercifolia

Sky will have over thirty varieties of H. macrophylla alone this year. Some to consider include: the Angel Series (ball-type flowers with a picotee edge); ‘Blaumese’, a stunning deep blue lacecap; Blackstem Hydrangea, whose beautiful black stems contrast nicely with the lush foliage and rose or medium blue flowers; and ‘Pia’, a dainty, compact plant topped with small pink heads. A great newer introduction is the revolutionary ‘Endless Summer’, which can be pruned (or frozen) to the ground and still bloom. Other hydrangeas bloom on old wood, so you end up pruning off flower buds; ‘Endless Summer’ and its brand-new pale sister, ‘Blushing Bride’, bloom on new and old wood for continued flowering. Another dramatic new macrophylla is ‘Lady in Red’—red stems, red leaf veins, burgundy-red fall foliage, and lacecap flowers that open pinkish white and turn rose as they age.

H. anomala petiolaris

With over 50 varieties of hydrangeas in stock, Sky Nursery can help you arrange a friendly takeover in your own garden. Come pick up our 2006 list or ask one of our knowledgeable staff to help you choose the plants best for your situation. Then sit back and enjoy all that hydrangea has to offer for the summer garden.

By Charlie Shull
Skylights Spring/Summer 2006 Vol. 21, No. 2

Other articles on the art of gardening

Other articles on trees and shrubs