Posted By: Rebecca van der Zalm in
Shrubs
Hydrangeas are a lovely and diverse genus, many of which have become essential parts of our garden vocabulary.

Most of us are familiar with the "old fashioned hydrangea": hydrangea macrophylla, and mostly with it in its round headed (mob-cap) form. In England, this variety is called "mob-cap" after the rounded cap worn indoors by married women in the late 18th/early 19th century. Here in North America, they are more usually called mop heads. Having grown up in an English tradition, I found this very odd at first!!

This shrub has a lot going for it: it flowers for a very long time starting in the summer when few shrubs but roses are in bloom. Unlike the rose it is equally happy in sun and in shade, though it requires more water in full sun. And, also unlike the rose, it needs no deadheading or summer pruning; the round flowers of macrophylla are lovely from the time they first appear, often in strange shades of ivory & green, slowly deepening to their ultimate colours of blue or pink, and then, as fall approaches, evolving into yet stranger colours of violet, burgundy, wine and tan. These flowers dry well, and, if you like, can be sprayed with gold for Christmas decoration!

As well as mobcaps, hydrangea macrophylla has a lacecap form. Like the dogwood, what appears to be a flower is actually a bract surrounding the true flower, which is comparatively insignificant. In the mobcap above, the bulk of the flower is made of infertile bracts. In the lacecap, the centre of the flower is made up of tiny fertile flowers with a surrounding circle of bracts, looking much like a lace doily, or old fashioned lace cap, hence the name. These plants are generally more open and graceful in appearance than the mobcaps, but have many of the same attributes.
Both kinds of hydrangeas serve a good purpose in garden design. They fit very well with rhododendrons, liking the same conditions of soil and sun, and adding garden colour at a time when rhododendrons are long over. The lacecap is particularly nice here, its grace contrasting with the bulkier shape of rhododendrons. They fit equally well with the long blooming summer & fall perennials, adding some restful substance to the border.

In addition to these two forms of H. macrophylla, hydrangea paniculata (Peegee) is a treasured garden plant. Instead of a dome, the flowers form a cone, initially white (or green) deepening to rosy red and ultimately burgundy in a way reminiscent of macrophylla, but more striking because of the size of the flower. The plant too is larger with quite a different garden effect, with strong wands growing upwards. Often grown as a standard (("tree form") it makes a terrific central feature in a frontal bed.
Macrophylla in both its forms and paniculata are those most often encountered in gardens; but there are many others: hydrangea arborescens Annabelle (a very hardy form, blooming on new wood), hydrangea quercifolia (oakleaf hydrangea - very handsome in woodland), hydrangea aspera (extraordinarily shade tolerant) and of course, the climbing hydrangea: hydrangea petiolaris). These are all excellent plants but more suited to a wilder sort of garden than macrophylla and paniculata.
Some well established favourites:
Macrophylla : first the mobcaps
Sister Theresa |
pure white, each flower with a pale blue eye |
Nikko Blue |
very large turquoise, a bit floppy, but gorgeous in acid soil |
Glowing Embers |
reliably red in any soil |
Lovely Lacecaps
Blaumeise (Teller Blue) |
blue turning brilliant pink in basic (alkaline) soil |
Kardinal (Teller Red) |
rich deep pink turning purple in acid soil |
Libelle (Teller White) |
white with deep blue centre which centre turns pink in basic soil |
Paniculatas
Paniculata Grandiflora (the original PeeGee) |
pure white flowers aging rosy pink |
Limelight |
soft green aging to pink |
Brussels Lace |
a rare form with flowers like a lacecap white with no colour change |
Quickfire |
white flowers turning pinkish red |
For more information about growing Hydrangeas, read the Learn to Grow Hydrangeas Blog Post
If you're interested in any of these beautiful Hydrangeas, drop by the nursery and check out our collection. As always the selection and availability is always changing so call ahead if you're making a special trip