A hydrangea is a hydrangea, is a hydrangea, is a hydrangea…
Hydrangeas, those great flowering shrubs, were thrust into the headlines a while back when singing celebrity Madonna publicly dissed a fan’s gift of a bouquet of beautiful blue blooms. While the “material girl” may “…hate hydrangeas,” a whole lot more of us are simply gaga over them. I know that for a fact because I see blooming hydrangeas everywhere, and they’ve been especially pretty this summer. What’s not to like about hydrangeas? Big showy blooms that last for weeks, foliage that stays green all season and ease-of-culture with few pest or disease issues add up to a megastar of a shrub that is making horticultural news on its own merits.
The news is that innovative hydrangea varieties are popping up like mushrooms. Add them all up and it is enough to make anyone’s head spin. There are variations of big leaf and small leaf and oakleaf, reblooming, climbing and tree hydrangeas — and that’s just the tip of the hydrangea-berg. Don’t even get me started on flower types, colors and shapes like mopheads and lacecaps, Annabelles and Paniculatas (which frankly sound to me more like tropical cocktails than shrubs), blues, pinks, whites, reds, even greens. Then there are dwarf plants, re-blooming, plants with different bloom times and even more new varieties arriving all the time. There’s a galaxy of choices out there, and you better believe it that these aren’t your mother’s hydrangeas.
One online source lists 140 different varieties of hydrangeas. How is anyone expected to pick the right one for their garden? And is there really any difference between all those hydrangeas? Or is a hydrangea just a hydrangea? I for one could use some simplification on this hydrangea family tree issue, a road map to help understand their differences and needs and qualities.
Many of the hydrangeas we grow here are native to Asia, and others — like oakleaf and the smoothleaf hydrangeas — are native to North America. Hydrangeas are deciduous perennial shrubs with low woody branches, and include varieties that grow well in zones 3 through 9. Hydrangeas do best planted in a rich, well-drained but moist growing environment, and many tolerate light shade, though most prefer several hours of full sun per day. (On the other hand, I have seen hydrangeas growing quite happily in deep shade in the Virgin Islands, which would be a Zone 12 or 13.)
For some hydrangea varieties bloom colors are affected by soil pH, while others aren’t. Some hydrangeas should be pruned and others not. While there are many species of hydrangeas, basically there are five categories of hydrangeas that we grow here. Here’s a rundown of those five that includes pruning, flowering characteristics and cultivation information:
• Hydrangea anomala petiolaris — The climbing hydrangeas are slow-growing, shade-tolerant and cold hardy to Zone 4 with lacy white blooms and deciduous foliage on clinging woody vines.
• Hydrangea arborescens — Native to North America, the smoothleaf hydrangeas bloom on “new wood” and should be cut back in late winter or early spring to encourage new growth to produce flowers. Cold hardy to Zone 3, smoothleaf varieties include blooms of both the mophead and lacecap forms. Notable new choices include “Incrediball” with huge balls of pure white on sturdy stems and “Invincible Spirit” with mounds of deep pink “Annabelle” hydrangea blooms that mature to a soft pink and are produced until frost.
• Hydrangea macrophylla — The “bigleaf” hydrangeas have showy blooms both mophead (full and round, some doubles) and lacecaps (lacy swirls) on deciduous shrubs. Most are cold hardy to Zone 5. Standouts in this category are Cityline “Venice” with deep blue double florets, Cityline “Berlin” with deep pink florets rimmed in white, and reblooming hydrangeas Endless Summer “Blushing Bride” with double white picote blooms that blush to a pale pink and Let’s Dance “Starlight” with blue lacecaps. Bigleaf hydrangea bloom colors are affected by soil pH, and many set their buds on “old wood” — the previous season’s growth — so cutting them back in the fall or spring prevents them from flowering. Newer varieties like those in the Endless Summer collection bloom on both new and old wood.
• Hydrangea paniculata — These are known as “hardy hydrangeas,” or PeeGee or tree hydrangeas. Cold hardy to Zone 3, they are more heat-, drought- and sun-tolerant than the bigleaf varieties. Their bloom colors are not affected by soil pH. Paniculata refers to the flower head shapes, which are cone-shaped. These hydrangeas, which can be either shrubs or tree form, bloom on “new wood” and should be cut back in late winter or early spring to encourage new growth to produce flowers. Look for a simply charming new dwarf called “Bobo” that covers itself in white pompoms, and grows to just 30 to 36 inches tall.
• Hydrangea quercifolia — Slow-growing and eventually forming large shrubs, the oakleaf hydrangea is native to the Southern U.S. and is cold hardy to Zone 5, tolerating a wide range of sun exposure conditions. This variety prefers a moist, rich, well-drained slightly acid growing medium. The characteristic oakleaf-shaped foliage often turns a rich bronze or red in the fall. New compact “Ruby Slippers” has large spikes of deep pink blooms.
Now that we have that cleared up, but not to muddy the waters, there are a couple more hydrangeas I’d like to mention: the bracted hydrangeas (Hydrangea involucrata); and a rather rare one, Deinanthe caerulea that is great for shaded gardens. The first is only cold hardy to Zone 6, but blooms on “new wood” and produces lacy delicate blooms every year, making it suitable for only the most protected of sites in this area.
The second is a member of the Hydrangeaceae family; it is native to China and its clusters of downward facing waxy blue blooms are other-worldly. It prefers rich and moist, but well-drained soils and rewards the gardener with beautiful form, crinkly-textured deep-green foliage and intriguing blooms. Hardy to Zone 4, this unusual member of the Hydrangea family makes a stunning woodland plant.
That pretty much covers it for the hydrangea department, but you’ve probably noticed that there is one loose thread that needs tying — Madonna’s apology. Being a big-time star who depends upon faithful, adoring fans for her livelihood, you can bet she eventually came up with something to say for her rude reaction to what must have been a thoughtful gift. So she apologized — if you can call it that. Here’s what Madonna said:
“If I could take back my words I would, but I can’t, so what am I left with? I’m left with the fact that I still hate hydrangeas! And I will always hate them! It’s a free country! So f–k you, I like roses!”
Well, bless my stars! That’s the first (and last) time you’ll ever see something like that in this column. Now there’s someone who is passionate about the flowers she likes and dislikes, even if she doesn’t understand how to issue an apology. Aside from that, she is so wrong about hydrangeas. They are definitely worth liking, if not loving. Madonna, on the other hand, I’m not so sure about.
Cutting and drying hydrangeas
From Proven Winners ColorChoice comes this advice on drying hydrangeas to enjoy in everlasting arrangements and crafts projects. First cut the flowers when they are slightly past their peak. Place flowers in a vase and allow them to dry while in water, which helps the flowers to hold their shape and color as they dry.
Lynette L. Walther is the recipient of the Garden Writers Association’s Silver Award of Achievement for 2012, National Garden Bureau's Exemplary Journalism Award and the Florida Magazine Association's Silver Award of Writing Excellence. She is a member of the Garden Writers Association, and she gardens in Camden. Got questions, or comments? Visit her blog, and join in the conversation at: gardeningonthego.wordpress.com or “friend her” on Facebook.