Red-twig dogwoods

Horticulture Highlight: Red-twig dogwoods, Cornus sericea, Cornus alba
…Everyone longs for love’s tense joy
and red delights…
-Jane Kenyon
A sampling of red delights from past Horticulture Highlights could include blossoms of rufous-tinted hellebores, redbud, tree peony, azalea, rose, rhododendron, cardinal flower and mums, with the added autumn foliage of maple, franklin tree, Virginia sweetspire, sourwood, tupelo and fothergilla as a partial list.
However, none of the above provide their “red delight” display during our winters. So we look towards our red-stemmed or red-twig dogwoods, members of the genus Cornus. Many are familiar with America’s springtime flowering dogwood or Asia’s summer flowering kousa dogwood, fewer may also know the indistinctly named cornelian cherry. These three small trees are arborescent members of the botanical genus Cornus which includes far more numerous shrub species. Recent and ongoing taxonomic examinations allow the ambiguous fact stating there are 30 to 60 species within this genus.



None the less, herein we introduce two frequently planted species, each with notable red stem color during winter months, Cornus sericea, redosier dogwood of North America and Cornus alba, Tatarian dogwood from Siberia, Manchuria and northern Korea. Nearly indistinguishable, Michael Dirr, author of the inimitable Manual of Woody Landscape Plants, states therein “…the red-stemmed dogwoods are difficult to separate by winter characteristics especially as small plants and one is never absolute as to which species he/she is purchasing…”. The dominant winter characteristic referred to is a discernable color transformation of their woody stems from a greenish to a blood red, with many cultivated varieties exhibiting varied hues from bright coral to bold crimson to beet-red. All shades of red-twigs are strikingly enhanced when surrounded by snow.
Snow,
blessed snow,
comes out of the sky
like bleached flies.
The ground is no longer naked.
The ground has on its clothes.
The trees poke out of sheets…
-Anne Sexton
There are strong similarities in the appearance of leaves, flowers and fruits of these two species. The branching patterns are opposite as with most members (not all) of this genus. The 2-5-inch-long leaves of both species are smooth-edged (entire margin) with 5-6 pairs of veins curving parallel to the margins. Both provide an attractive reddish-purple fall foliage.
Unlike the large petal-like bracts found on flowering dogwood and kousa dogwood, flowers on these two species as with many other dogwoods appear as small heads of multiple whitish-yellow flowers forming a flat top referred to as a cyme. When successfully fertilized these flowers later develop ½-inch, whitish/slightly bluish fruits (drupes) that are relished by many bird species and hence are not long persistent.
On a winter visit to Mount Auburn look for our Red-twig dogwoods on Story Road, Willow Pond Knoll, Rosebay Avenue, above Narcissus Path, Anemone Path and off Meadow Road.
Oregon Grape

The greatest service which can be rendered any country is to add a useful plant to its cultivation. – Thomas Jefferson
Oregon Grape, Mahonia aquifolium is a good example of Jefferson’s (1743-1826) oft-stated opening quote. This plant of contemporary usage was introduced as part of our country’s early botanical exploration.
Today we may add Oregon Grape to a list of more well-known evergreen shrubs such as rhododendron, mountain laurel, yew and pieris. Averaging 3 to 6-feet high and wide, its distinct alternate compound leaves are composed of 5 to 9 shiny, stiff, leaflets, each 1 ½-to-3 ½-inches long with spines on the tip and margin. Bright yellow, slightly fragrant flowers occur in mid-to-late April, about the same time as some of our flowering magnolias and cherries. Later in August-September these flowers may produce dark-blue berries, looking somewhat akin to grapes, hence the common name. Fruits may be used for jellies, wines and were historically part of traditional diets of indigenous Pacific Northwest peoples.
(more…)Flora Mount Auburn
We are excited to announce the public release of Flora Mount Auburn, our online plant collections database. For the first time, visitors can search our entire collection of trees, shrubs, perennials, and groundcovers….more than 15,000 plants!
Get a preview of FLORA with Samantha Richardson, Plant Records Manager:
Mount Auburn’s staff collaborated with Blue Raster, LLC, BG-BASE’s Mike O’Neal, and Brian Morgan with the Alliance for Public Gardens GIS (APGG) on the creation of FLORA MOUNT AUBURN.
This project was made possible in part by the Institute of Museum and Library Services (MA-30-17-0309-17).

Panicle Hydrangea, Hydrangea paniculata

It was late in September when you took me
To that amazing garden, hidden in the city,
Tranquil and complicated as an open hand, …
– May Sarton
For many of us, September, with its return of school-days, has become a de facto end of summer. One late-blooming plant, that always extends the lushness of summer flowers, well past Labor Day, is the Panicle Hydrangea, Hydrangea paniculata.
The genus Hydrangea, within the family HYDRANGEACEAE, includes over 70 species of flowering plants, native to south, and eastern Asia, and North, and South America. Hydrangeas are divided into three major groups of plants: vines; shrubs with the flower inflorescences as round, or conical clusters; and shrubs with flat-topped inflorescences. Hydrangea paniculata, with flowers in elongated, conical, terminal clusters, is native to China and Japan, and was introduced into western cultivation in 1861, by Philipp Franz von Siebold (1796-1866), German physician, and notable plant collector.