Mauve Sleekwort

A not-very-good photo of Liparis lilifolia. Its brownish flowers are difficult to spot in the leaf litter and even harder to photograph satisfactorily.

After sixteen years, I thought I had found all of the interesting plant species growing on our property, so I was very surprised to stumble across a flowering specimen of Liparis lilifolia yesterday evening. This species is known as the lily-leaved twayblade orchid, but I prefer its alternative common name, mauve sleekwort.

L. lilifolia grows at scattered locations throughout the mountains, piedmont, and coastal plain of North Carolina, and its range extends over much of eastern North America, from Quebec and Ontario south to Georgia. Its flowers are visited by flies, although they are not pollinated very frequently. Coincidentally, one of my neighbors had emailed earlier in the week to say she had found the species on her property, so today we served as orchid matchmakers and attempted cross-pollination with toothpicks.

My plant is growing in the woods outside our deer fence, so I have covered it with a wire cage while we wait to see if viable seed will be produced. And now, I’m wondering what else I have overlooked in the leaf litter.

Hillia triflora and the bird pollination syndrome

photo of Hillia triflora flowers
Hillia triflora flowers in the typical cluster of three at the end of a branch

Hillia triflora is a somewhat obscure epiphytic shrub in the coffee family, Rubiaceae. I didn’t know it existed until I ran across a small cutting for sale on eBay a few years ago, and after a quick google search, I made certain that I would be the high bidder when the auction ended. It’s a hummingbird-pollinated plant, and as I have noted before, this gardener is attracted to the same floral features that attract hummingbirds.

H. triflora comes from central America, with specimens collected from southern Mexico to Colombia, and although it usually grows at higher elevations, plants have been found at only 100 m above sea level in Costa Rica [1]. As might be expected from this wide geographical and altitudinal range, the plant seems to be quite tolerant of both summer heat outdoors and cool winter nights in the greenhouse. There are two subspecies with overlapping range, H. triflora subsp. triflora, and H. triflora subsp. pittieri; judging by the equally sized leaves on flowering shoots and narrow, uninflated flowers, my plant belongs to the nominate subspecies [1].

The growth habit of this plant is very interesting. It forms an open shrub with flexible, infrequently branched stems bearing opposite, semi-succulent leaves. Each stem terminates with a protective sheath. Over the course of a couple of months, the sheath slowly swells and eventually splits, revealing that it was formed by a pair of bracts tightly pressed together. Emerging from the sheath is either a new stem segment with a pair of leaves and new sheath, or a cluster of (usually three) flower buds. At the base of the flower buds is one or more new sheaths, so the stem sometimes branches after flowering.

photo of the sheath at the end of the branch
Sheath at the end of a branch. At this stage in its development, it is difficult to see that it is composed of two bracts.

The roots of H. triflora are fibrous, without obvious adaptations to epiphytic life, and plants in habitat are occasionally found growing terrestrially in leaf mould or rotting wood [1]. Consequently, I added some coarse peat to the mix of orchiata bark and perlite in which I potted my plant. I water when the mix is almost dry, and so far the plant seems happy. It grows with my vireyas under shade cloth in summer and goes back in the greenhouse when temperatures drop below 50 F (10 C) at night.

The flowers of H. triflora are very similar to those of the unrelated coral honeysuckle, Lonicera sempervirens (Caprifoliaceae), that grows wild in the woods around my house–it’s a remarkable case of convergent evolution driven by birds. I would guess that the hummingbird responsible for pollinating H. triflora is roughly the same size as the ruby-throated hummingbirds (Archilochus colubris) which pollinate L. sempervirens. I suppose it is even possible that A. colubris is a pollinator of H. triflora, given that the birds over-winter in central America and H. triflora has flowers in November/December as well as March-May [1].

photo of coral honeysuckle flowers
Lonicera sempervirens flowering at the edge of our woods today

comparison of L. sempervirens and H. triflora flowers
Lonicera sempervirens (top) and Hillia triflora (bottom)

I have previously featured a variety of hummingbird pollinated flowers on this blog, both native plants (Aquilegia canadensis, Aesculus pavia, Lobelia cardinalis, Lonicera sempervirens, Spigelia marilandica, Silene virginica) and tropicals (Juanulloa mexicana, Macleania sp. aff. smithiana, Macleania pentaptera, Ceratostema glans, Cavendishia capitulata, Bouvardia ternifolia, Bessera elegans, Behria tenuifolia, Columnea microcalyx, Columnea crassifolia). These flowers share obvious characteristics: bright red/orange/magenta color, tubular (or sometimes bell-like) shape, lack of fragrance, and copious nectar. The same features are seen in plants from Africa, Asia, and Australasia where there are no hummingbirds. In those locations, sunbirds (Nectariniidae) and honeyeaters (Meliphagidae) fill much the same ecological niche. However, because sunbirds and honeyeaters are less likely to hover than hummingbirds, bird-pollinated flowers in the old world are usually not pendant and are often attached to a stout inflorescence that allows the birds to perch (see, for example, Cyrtanthus obliquus).

photo of flowering Dermatobotrys saundersii
Dermatobotrys saundersii is an epiphytic shrublet from South Africa that is likely pollinated by sunbirds. It is easy to grow from seed but seems not to like hot North Carolina summers. I have been unable to keep plants going for more than a couple of years.

flowers of Dendrobium chrysopterum
The flowers of Dendrobium chrysopterum from New Guinea bear all the hallmarks of bird pollination. Like similar Dendrobium orchids, they may be visited by honeyeaters.


  1. Taylor, CM (1989). A revision of Hillia subg. Ravnia (Rubiaceae: Cinchonioideae). Selbyana 11: 26-34.

Six on Saturday #74 (April 22, 2023)

Happy Earth Day! This would be an obvious day for working in the garden, but unfortunately we will have thunderstorms rolling through for most of the day (though luckily the potential for tornadoes seems to be southeast of our location). Here are a few pictures taken this morning before the rain, rounded out with a couple taken earlier this week.

1. Paeonia ‘America’

Photo of Peaonia 'America' flower

I planted this herbaceous peony about three years ago. It produced its first buds last year, but they all froze and aborted. This year, two buds survived, and I finally have the first flower. Each day, the flower starts to open after I leave for work and closes before I get home, so it was tricky to get a photo. The flower is already closing in this picture, and I only saw it partially open because I left work early to catch eldest offspring’s last high school tennis match.

2. Paeonia obovata (Japanese woodland peony)

photo of white Paeonia obovata flower

This peony does well the shade under a dogwood, where it grows among trilliums and Calanthe orchids. The white-flowered form sometimes goes by Paeonia japonica, but Kew lists that name as a synonum of P. obovata.

3. Calycanthus floridus (eastern sweetshrub, Carolina allspice)

Photo of Calycanthus floridus flowers and leaves

This native woodland shrub is famed for its fragrance, which is often compared to fresh strawberries. My plant smells more like overripe fruit–not horrible, but not something I’d seek out. If buying one to grow close to the house, it’s probably best to shop for plants in flower and give them a sniff test before laying down your money.

4. Actias luna (luna moth)

Luna moth with damaged wings

Luna moths only live for a few days after completing metamorphosis, and this one was at the end of its lifespan. It could no longer fly, and was fluttering weakly across the lawn this morning.

5. Quercus phellos (willow oak) growing on Juniperus virginiana (eastern red cedar)

photo of willow oak growing from the trunk of a red cedar tree

Not in my garden, but local, are two of my favorite individual trees. The pale green leaves are a small willow oak which is growing epiphytically on a red cedar. The oak must have grown from an acorn that fell or was deposited by a squirrel into a crack in the trunk of a red cedar. Enough water and organic debris sifts down to keep the oak alive, and I have been watching it grow slowly for almost a decade. Each spring, it’s always encouraging to see that the little oak has survived another year.

6. Allium schoenoprasum (chives)


Garlic chives, Allium tuberosum, seem to be more vigorous in this climate, but this little clump of chives is doing fairly well. It’s in a raised bed shared with walking onions and garlic chives, which are permanent residents of the bed, and two varieties of garlic (softneck and hardneck), which will be harvested in June.

Jim at Garden Ruminations is the host of Six on Saturday. Head over there to see his Six for this week and find links to the blogs of other participants.

Cemetery Iris


Iris albicans, the white cemetery iris, is a fairly plain, average-looking bearded iris, and its flowers, though a pristine white apart from the yellowish beard, cannot hold a candle to more intensely colored hybrids. So why bother to grow it? It’s the backstory that makes this plant interesting. I. albicans is reported to be sterile and is thought to be a natural hybrid of two species native to the Arabian peninsula. It is widely naturalized along the Mediterranean coast as far as Spain and Portugal and may have been cultivated, and propagated by division, for >1000 years. The story goes that the plants were carried from their original Arabian homeland during the Muslim conquests of Anatolia, north Africa and Spain, and they were traditionally planted at grave sites, a practice that continued among Christians when Spaniards brought the plants to the new world following the Reconquista.

So, that’s the story. It’s romantic and even plausible given what is known about the plant’s distribution, and more-or-less the same tale has been repeated in books and journals for the past century (see here for an early example in the Bulletin of the American Iris Society, October, 1925). There are a few holes in the narrative, though. As far as I can tell, there are no primary sources documenting the spread of I. albicans through the Muslim lands during the middle ages (not that we would expect there to be), and no one seems to know the species that were its putative parents.

But it’s a great story. I, for one, am going to assume it is true.

Physically, I. albicans is a fairly small bearded iris. Its gray-green foliage is more compact than the more modern hybrids that circulate among North Carolina gardeners, and the inflorescence is likewise short with stubby branches. The buds form very early in the year and are often damaged by freezing weather. Last year, they all froze just before opening. This year, we had generally mild weather in February and March, and I managed to see some flowers by covering the plants with buckets on several nights in late March when the temperature dipped below 28 F (-2.2 C). I think it’s at close to its northern limit in my garden, and the plants seem to be more commonly grown in the gulf coast states.

Six on Saturday #73 (April 1, 2023)

It’s been a while since I have had the time to put together a Six on Saturday post. Spring is well underway here in the North Carolina piedmont. The early Narcissus have long finished flowering, and only late-flowering clones like ‘Thalia’ and ‘Golden Bells’ are still in bloom. Azaleas are just getting started. The native pinxter flower, Rhododendron periclymenoides is in full bloom, and the buds are opening on Florida flame azalea (R. austrinum). My hardy Calanthe and Bletilla orchids were hit hard by a freeze after a prolonged frost-free spell, and many of their new growths were turned to mush. It remains to be seen how many flowers they’ll make this year.

Here are six plants from the greenhouse and garden that I haven’t featured before.

1. Rhododendron ‘Aravir’


‘Aravir’ is another of the modern vireya (tropical Rhododendron) hybrids. Its parentage is R. konori x (‘Pink Delight’ x jasminiflorum), which explains its similarity to the Victorian ‘Princess Alexandra’ (R. ‘Princess Royal’ x jasminiflorum). The parentage of ‘Pink Delight’ is unknown, but it was an old Veitch hybrid, so probably similar to ‘Princess Royal’. I got this plant as an unrooted cutting about 2 1/2 years ago, and this is the first time I have seen it flower. I am currently experiencing (hopefully temporary) post-COVID anosmia, so I can’t say much about its fragrance. I can barely detect a scent, which probably means that it is very strongly scented. Like all vireyas, this plant is not frost-hardy. I grow it in the greenhouse in winter and outdoors under shade cloth in summer.

This is one of a group of vireya hybrids with names drawn from the Chronicles of Narnia. ‘Aravir’ refers to the Narnian morning star.

2. Columnea crassifolia


This beautiful epiphytic gesneriad is from Guatemala, so it is a greenhouse plant. The large hummingbird-pollinated flowers are similar to its relative C. microcalyx (syn. gloriosa), but while the stems of C. microcalyx hang limp or creep along a surface, those of C. crassifolia are rigid. This plant flowers most of the winter and on-and-off during the summer. Like R. ‘Aravir’, it goes outside under shade cloth once the danger of frost is past.

3. Taraxacum albidum (Japanese white dandelion)


When growing dandelions for chicken snacks and salad greens, it’s fun to try unusual varieties. Last year we flowered the pink dandelion (Taraxacum pseudoroseum), and this year white dandelions are getting started. Taraxacum pseudoroseum wasn’t very pink, but T. albidum is definitely a more pure white. Since dandelions can be persistent weeds, we keep them in pots and clip off inflorescences before the seeds are mature.

4. Camellia ‘Rosehill Red’

Rosehill Red

Not much to say about this; it’s a very nice Camellia japonica cultivar. I tend not to like double and semi-double flowers, but these ones aren’t too fussy looking. It is beside Camellia ‘Yuletide’ which flowers in early winter, so I get an extended shot of red color in that part of the garden.

5. Muscari armeniacum ‘Touch of Snow’


These little guys that I planted last autumn are a little difficult to find in the garden, but they’ll become more obvious as they start to form clumps. They make a nice change from the more typical purple grape hyacinths.

6. Hyacinthus ‘Woodstock’


I had a little trouble finding six flowers that I hadn’t featured before, so I’ll slip in these hyacinths which actually flowered a couple of weeks ago. Like the Muscari ‘Touch of Snow’, I planted them last autumn, so this was my first look at the flowers. My wife was the one who picked them out of the catalog, but I very much like the intense magenta color which darkens to purple at the base of the flower. Quite possibly my favorite Hyacinth now.

Jim at Garden Ruminations is the host of Six on Saturday. Head over there to see his Six for this week and find links to the blogs of other participants.