A garden oasis and cultural center overlooking the Hudson River

Raptor-ous Spring Birding!

Horticultural Interpreter Alison Filosa works with Charles Day and the rest of Wave Hill’s Public Programs Department.

Naturalist Gabriel Willow led his monthly birding walk this past Sunday with 35 adults and three children joining him. We started on an exciting note with the sighting of an immature or juvenile bald eagle, distinguishable from a mature bird by its brown and white coloring and its large, white beak. It turns yellow as it ages. A Cooper’s hawk was seen flying near the Perkins Visitor Center, along with starlings, blue jays and house finches.

Drawn to the Conifer Slope by sound of blue jays, the group experienced the rare sighting of a barred owl, native to eastern North America, in one of the conifers. Gabriel has only spotted a barred owl three times at Wave Hill in the 14 years he’s been leading our birding walks, so it was a special treat for all! Wave-Hill_Raptor-Day_credit-Joshua-Bright-for-blog

This shot by photographer Joshua Bright was taken on Wave Hill’s 2010 Raptor Day, during a demonstration by Volunteers for Wildlife.

Off the owl soon flew, leading the group to spy a red-tailed hawk, perched quietly on a tree along the Shade Border lawn.

High up over the Hudson River, off to the west, a migratory turkey vulture was spotted, its wings upswept. Also spotted over the river was a raven, possibly one of the pair that live on the George Washington Bridge,

Today was obviously a very fine day to see raptors and other migratory birds, not to speak of juncos, robins, sparrows and our local mockingbirds, and our group left enthusiastically anticipating May’s walk, scheduled for Mother’s Day.

Plant of the Week: Cornus officinalis ‘Kintoki’ (Japanese Cornel Dogwood cultivar)

Charles Day is Wave Hill’s Ruth Rea Howell Senior Horticultural Interpreter.

This lovely, small tree is a cultivar of the Japanese cornel dogwood (Cornus officinalis ‘Kintoki’). Although related to our native flowering dogwood (Cornus florida), it is much closer in appearance to the cornelian cherry dogwood (Cornus mas) of Europe and Western Asia.the-tree-smaller

A good, all-year “performer,” it has clusters of tiny, yellow flowers in early spring, bright-red fruits that set against lustrous orange-red foliage in fall, and peeling, reddish-gray bark that looks superb in the clear light of winter.close-up

Both of the cornel dogwoods (C. officinalis & C. mas) have yellow flowers in March or early April and might be confused with the slightly later-blooming—and more lemon-yellow—forsythia (Forsythia spp.).

Our specimen of the Japanese cornel can be seen blooming this week at the Kerlin Overlook, the terrace between the Perkins Visitor Center and the Aquatic Garden. The first shot below was taken looking west towards the Hudson River, the second looking east toward our Wild Garden.setting-looking-westsetting-looking-east

Plant of the Week: Helicodiceros muscivorus (Dead Horse Arum)

Charles Day is Wave Hill’s Ruth Rea Howell Senior Horticultural Interpreter.

This oddity of the plant world has some of the same odoriferous qualities as its relatives, the famous—and huge—titan arum (Amorphophallus titanum) and the Voodoo lily (Sauromatum venosum), which some gardeners in the northeast U.S. grow as a curiosity.

Growing from a tuberous root, the dead horse arum (Helicodiceros muscivorus) unfurls its leaves in early spring and produces a single, large bloom shortly after.the-plant

The flower is a spathe-and-spadix type, typical of the arum family. The spathe is the large, scoop-shaped structure and the spadix is the spike in its center.close-up

The hairiness seen on the flower of this species is not typical of the family, but the surprisingly unattractive aroma—it’s called dead horse arum for a reason—is not so unusual. Many arums are pollinated by the kinds of flies which are attracted to carrion. If a flower smells like rotting meat (or something worse), it will attract these potential pollinators. Another surprising ability of this plant is that it generates heat as the flowers mature and emit their scent. This seems to make them even more irresistible to the unsuspecting flies, which probably imagine they have found a warm and wonderful, freshly decomposing mammal carcass to lay their eggs on.


The specific epithet, muscivorus, suggests that this plant eats flies, but this is not entirely the case. The true flowers (or florets), both male and female, are tiny and arranged around the central spadix. The female florets open first and attract the attention of their insect suitors, and then trap them within minute hairs for just long enough for the male florets to mature and release their pollen, usually a day later. By the time the flies are released, they are coated with pollen and ready to go straight to the bloom of the very next stinky dead horse arum they detect. Apparently, the aroma is so attractive that the experience of being imprisoned is instantly forgotten.

The genus name, Helicodiceros, is from the Greek for twisted horn, which describes the shape of the flower just before it opens.

It is native to the coasts of the Mediterranean islands of Corsica, Sardinia and the Balearics of Spain. Our plant spent the winter in the protection of the Marco Polo Stufano Conservatory, but has been put on display outdoors, for obvious reasons. See it just inside in the T. H. Everett Alpine House—and don’t wait!


This last shot is of Wave Hill gardener Susannah Strazzera, who has been minding our dead horse arum since we acquired it ten years ago. It’s been a long ten years waiting for it to bloom, and her excitement has been contagious: staff wander over to the Alpine House mid-morning to check out this horrible wonder.Susannah


Plant of the Week: Aloe greatheadii var. davyana (Spotted Aloe)

Charles Day is Wave Hill’s Ruth Rea Howell Senior Horticultural Interpreter.

South Africa has a wide range of climates and a variety of plant habitats. The Western Cape, for example, is noted for its hot, dry summers and mild, moist winters. Other regions, including the grasslands of the high veld, experience cool, very dry winters and warm, periodically wet, summers.

This climatic variation explains the differences in the growth cycles of South African plants. Those that have to endure the summer droughts of the Cape are active in the winter months but go completely dormant in the summer. Plants that make their home on the veld, such as this spotted aloe (Aloe greatheadii var. davyana), are dormant during the dry winters and do all their growing in the summers.

Towards the end of winter dormancy, however, the spotted aloe (and many of its kin), will flower even when the landscape is still parched. Despite showing signs of drought-stress—with dried and shriveled leaf-tips—it is still capable of producing healthy spikes of yellow-orange blooms that stand up tall and obvious in the tinder-dry landscape.shrivelled-tips-2

This seemingly odd behavior ensures that the flowers get the undivided attention of any native pollinating bees and birds in the area, thus increasing the chance of successful seed production.

Our own plant in the Cactus and Succulent House, the right-hand wing of the Marco Polo Stufano Conservatory, has three, fine, flower spikes this year and is surrounded by other aloes that are also starting to bloom.the-plant

the-settingA note for the truly botanically interested: Aloe greatheadii var. davyana was formerly known as A. verdoorniae, and some taxonomists now recognize it as A. davyana.

Plant of the Week: Crocus tommasinianus

Horticultural Interpreter Alison Filosa works with Charles Day and the rest of Wave Hill’s Public Programs Department.

Crocus tommasinianus is otherwise known as snow crocus as it is one of the first crocuses to bloom.the-close-up

Originally found on the hillsides of Hungary, this small, dainty, purple crocus sticks its head up before the last snowstorm in March. It usually blooms in late winter to early spring and grows to 4 inches tall.the-plant

This early spring, two nor’easters have occurred as the crocus have emerged from the ground here at Wave Hill. Together with Eranthis hyemalis (winter aconite) and the Adonis amurensis (Adonis/pheasant’s-eye), it’s the first—and very welcome—sign of spring. Look for it along the path to the Wild Garden and in the Wild Garden itself.the-setting

The specific epithet name of Crocus tommasinianus honors Muzo Guiseppe Spirito de Tommasini (1794–1879), a botanist from Trieste.

Plant of the Week: Pelargonium crithmifolium (Samphire-leaved Pelargonium)

Charles Day is Wave Hill’s Ruth Rea Howell Senior Horticultural Interpreter.

Pelargoniums—familiarly called “geraniums”—come in many shapes and sizes. Almost all are native to Southern Africa and some of them come from surprisingly dry habitats.

The sturdy-looking, samphire-leaved pelargonium (Pelargonium crithmifolium) is one of the largest of all pelargoniums. It can grow to nearly four feet high, and is very well adapted to the conditions of its homelands in the Northern and Western Cape of South Africa.the-plant

It has thick, succulent stems and a drought-deciduous habit, both features that enable survival during hot and dry summers. By shedding its leaves before the onset of drought, moisture loss is kept to a minimum and the thickened stems function as water-storage devices.the-stem

Although devoid of foliage during its dormant period, it is able to continue photosynthesis thanks to the presence of chlorophyll in its green-tinged bark.

The mild winters bring rain and the possibility of growth. New leaves unfurl in late autumn and flowers appear by early spring—as can be seen this week in the Cactus and Succulent House, the left-hand wing of the Marco Polo Stufano Conservatory.close-up

If this piques your interest, plan to visit on Scented Geranium Day, Sunday, July 8. We’ll be looking at the astounding varieties and fragrances of Pelargonium species and hybrids in Wave Hill’s gardens, learning how to cook with geraniums and making soap using geranium oil.

Plant of the Week: Draba sp. (Whitlow Grass species)

Charles Day is Wave Hill’s Ruth Rea Howell Senior Horticultural Interpreter.

This little, yellow-flowered, whitlow grass (Draba sp.) in Wave Hill’s T. H. Everett Alpine House was grown from seed exactly a year ago. It appeared among a batch of gentian seedlings and was spotted by one of our sharp-eyed gardeners.the-setting

Once separated from its foster-family siblings, it was given individual attention and has now rewarded us by blooming profusely this spring.the-plant

close-upDespite the misleading common name, whitlow grass is not a grass but, in fact, a member of the mustard and cabbage family (Brassicaceae). There are more than 300 species of whitlow grass, most of them found growing wild in the mountains of North America, North Africa, Europe and Southwest Asia.

In medieval times, certain plants of this genus were used in the treatment of whitlows—painful inflammations on fingertips and toes.

Plant of the Week: Crassula rupestris (Concertina Plant)

Charles Day is Wave Hill’s Ruth Rea Howell Senior Horticultural Interpreter.

This week, our little concertina plant (Crassula rupestris) is putting on its annual display of neatly clustered pink flowers in the Cactus and Succulent House, the right-hand wing of the Marco Polo Stufano Conservatory.the-setting

close-upFound in the wild in some of the drier parts of South Africa and Namibia, it grows naturally in rocky places—rupestris indicates this affinity for rocks—and has several tricks to enable it to survive and spread in its arid environment. A slow-growing habit means that it requires less water than a more vigorous plant, and its thick, succulent leaves are able to retain moisture during prolonged droughts.leaves

Flowering is followed by the release of masses of tiny, dust-like seeds. In the wild, the lightest gust of wind would scatter them across the parched landscape. A small number might happen to lodge themselves in a crevice where water lingers following night dews or the occasional rain shower. If they are lucky, this might be enough to allow for germination and growth.

The genus Crassula contains hundreds of species from many parts of the world. All are succulents, but it is mainly the species from Southern Africa which are the most interesting for ornamental use. The name comes from the Latin Crassus, meaning solid or thick, alluding to their fleshy foliage.

Plant of the Week: Aeonium arboreum ‘Atropurpureum’ (Purple Tree Aeoneum)

Charles Day is Wave Hill’s Ruth Rea Howell Senior Horticultural Interpreter.

Blooming now in our Cactus and Succulent House—the right-hand wing on the Marco Polo Stufano Conservatory— is the purple form of the tree aeoneum (Aeonium arboreum ‘Atropurpureum’). It stands taller than most of the plants around it and is hard to miss—the flower spikes are large and very yellow.the-setting-2

The tree aeonium is native to Gran Canaria (one of the Canary Isles) where, despite the long dry summers there, it remains green and fresh-looking, even when neighboring plants might have turned brown or lost their foliage in an effort to conserve moisture. The genus name Aeonium comes from the Greek word aionios (eternity), not through any expectation that the plant will live forever, but because of this evergreen habit.close-up-2

Our purple form (‘Atropurpureum’) has dark-red, shiny leaves and these provide a striking contrast to the tight, conical clusters of yellow flowers.close-up-1

The branches of the plant that produce a flower stalk this year will die back in the coming weeks, leaving only the more youthful branches, which will continue to grow for future years.

Plant of the Week: Holmskioldia sanguinea ‘Bronze’ (Parasol Flower cultivar)

Charles Day is Wave Hill’s Ruth Rea Howell Senior Horticultural Interpreter.

This plant goes by several common names—parasol flower, Chinese hat plant, cup-and-saucer flower—all them alluding to the strange shape of its flowers. A narrow trumpet, formed by the tightly arranged petals, is backed by a wide, circular disk of fused sepals (the scales which covered the flower bud before it opened). This structure is called a calyx.close-up

Native to the tropical foothills of the Himalayas, it is a woody shrub with a semi-climbing habit and capable of growing to a height of ten feet. It can be kept much smaller when constrained in a flower pot, as can be seen in our Palm House, the central section of the Marco Stufano Conservatory.the-plant-and-the-setting

The normal flower color is bright red—hence the specific epithet of sanguinea (“color of blood”)—but this cultivar, Holmskioldia sanguinea ‘Bronze’, has pinkish-orange-colored flowers. The genus is named for the eighteenth-century Danish botanist Johan Theodor Holmskiold.