Rhododendron Thermometers

Can you tell how cold it is in winter by looking outdoors at your rhododendron? Locals in New Hampshire tell me that a quick glance out the window will indicate whether the temperature has dropped to 32° or not. When the temperatures drop to freezing, the normally horizontal rhododendron leaves begin to droop and curl.

The amount of droop and curl does correlate to the severity of winter temperature. The lower the temperature, the tighter the curl. At 20° they are curled as tight as they can possibly get. Our rhododendron leaves are drooped and tightly curled right now and that’s a clue to the frigid outdoor temperatures…. a -8° at daybreak and currently a -3°.

Junco on Rhody

But why do the rhododendron leaves droop and curl in the first place? Theories and debates abound. Some say it is to prevent branch damage from the snow load. Others theorize it helps prevent or reduce water loss in the leaves, although horticulturists and scientists dismiss this theory because the openings on the underside of the leaf are closed during the winter.

A likely reason is drooping and curling prevents rapid freezing and thawing of the leaves. If the leaves are horizontal as they are in warm months, thawing may occur on a sunny day in winter, then the leaves may quickly freeze again overnight. This quick freezing and thawing could destroy leaf cells. So possibly, the drooping and curling would be nature’s way to protect leaves from the thawing solar rays during the day.  They are better off staying frozen until they can thaw slowly.

Rhododendron

More study is needed to answer all the rhododendron leaf questions but I’m just happy to know I can rely on these magnificent shrubs to let me know when the thermometer hits 32°.

Rhododendron Fireworks

It was 39° in the garden this morning and I could see my breath in the air as I walked around the yard. Yet, cold,wet spring or not, we are on the verge of a HOT explosion of color. Rhododendrons are finally ready to burst into spectacular blooms. We are eager for the pizzazz and punch of color that the rhody brings. It will be glorious!

Here is a timeline of the last 10 days of bloom development in our yard.

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The Show is Over

Torrential rainfall, accompanying winds, then more rain, and a little more rain ended our rhododendron show too soon.

on the ground One by one, blooms slid along their pistils and fell to a heap in the grass.sliding bloomsWaterlogged blossoms still dangling from branches were visited by dozens of bees today. Competition was lively and the buzzing was a steady drone for most of the day.

bees Petal drop was everywhere. Lilac  and viburnum blooms are also finished and petals are decorating the grass in different shades. I am sorry to see the show end but never sorry to see a good spring rain.

What’s Blooming Now?

We’ve got rhodies! Four of them. And I’ve been excited for them to bloom. I’ve never had a rhododendron on any property I’ve lived and I was a little nervous about these. I read a release from the Cooperative Extension program at UNH that said most rhododendrons are too tender for New England weather. I also read about possible problems: Black Vine Weevil, sawflies, root rot, Petal Blight and Powdery Mildew.

Well, our variety must be a hardy one. All four of the rhodies are healthy and just beginning to bloom.  I have no ID on the species, but, I’m thinking  it could be Catawba (R. catawbiense), an evergreen that is about 7′ tall. Blooms have brownish speckles in the throat and, boy, are the blooms showy and huge!  Yes, it’s magic around this yard right now.

rhody...rhody.Rhodyrhody..

Race Against Time

There is nothing more beautiful in the spring landscape than an azalea, a member of the genus Rhododendron. Fifteen azalea species are native to the eastern part of our country and gardeners are becoming more appreciative and knowledgeable about them. Whether white, pink, red or orange or any combination of these colors, the native azaleas are said to be the most fragrant of all azaleas. These natives grow naturally in woodland settings beneath tall hardwood or pine trees where the sun is filtered and the soil is acidic.

In Gloucester, we feel fortunate to have fellow resident, George McLellan, a landscape designer who values the native azalea. He is a member of the Mid-Atlantic Chapter of the American Rhododendron Society and chairman of the Species Study Group. He knows his azaleas well, as he does everything else in the world of gardening including native plants, trees, bulbs, perennials, the uncommon, the rare and newest hybrids. He also knows his birds and is a regular on our birding walks where, if asked, will take time to share horticultural knowledge along the way.

Last week George also shared an azalea success story. Recently, on a tiny postage stamp plot of undeveloped land in Gloucester surrounded by a sea of man-made surfaces and buildings, a sign went up announcing the construction of a new fast food restaurant. George and fellow ARS member, Jim Brant, with no time to waste, took shovels to the tiny woodland site to save a native azalea.

Growing under the pines were Pinxter Azaleas (Rhododendron periclymenoides), a wild azalea found from Massachusetts to Georgia and Alabama. The name Pinxter is the Dutch word for Pentecost, named thus by the colonists because it bloomed on Pentecost, 50 days after Easter. It can grow to 6-8 feet tall with clusters of long-tubed pink to white flowers with a wonderful sweet fragrance. George and Jim were able to save some azaleas before dozers leveled the land, paved and built the restaurant in record time.

Protected in New York state, the species is obviously not safe from harm in Virginia. The azalea is certainly fortunate to have friends in need.

Ann Hohenberger, The Garden Club of Gloucester

The Azalea Gardens of Art and Betty White, Gloucester VA

Whites' Azalea GardenThese spectacular azalea gardens were created by Art and Betty White on the North River in Gloucester.  In the dappled light of loblollies and dogwoods, the Whites have created a natural wonderland of hundreds of mature azaleas and rhododendrons in a riot of colors.  Gentle paths lead to small ‘rooms’ inside the gardens where one can linger on benches to enjoy the splash of colors and individual blossoms. The Whites have generously opened their garden to friends each spring and have twice opened for HGW.  Over the years they have delighted in using their garden as a teaching tool to pass on their special propagation techniques to a multitude of gardeners.  Betty is a member of the Garden Club of Gloucester.

Whites' azaleas Whites' azaleasWhites' AzaleasWhites' AzaleasWhites' Azaleas

Ann Hohenberger, The Garden Club of Gloucester

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