Six on Saturday #24, April 7, 2018

We’re now in that liminal time when every frost could be the last, but we won’t know for sure until several more weeks have passed.  Yesterday was about 75 F (24 C), but snow is possible tonight.

In the woods, native redbuds (Cercis canadensis) and invasive Wisteria sinensis are in full bloom, and the dogwoods (Cornus florida) are just getting started.  In the garden, the first azalea flowers are opening, but most color still comes from spring bulbs.

Here’s what was going on in the garden and greenhouse this week.

1. Tulipa sylvestris (Woodland tulip)

T_sylvestris

Last autumn, I planted some bulbs of Tulipa clusiana var. chrysantha and Tulipa sylvestrisT. clusiana is supposed to be one of the best tulips for naturalizing in this climate, but I’m not sure how T. sylvestris will do long-term.  It’s possible that this floral show will be a one-time event if T. sylvestris doesn’t tolerate heat and humidity.

2.  Narcissus willkommii

N_wilkommii

Another new addition to the garden.  N. willkommii is one of the smallest Narcissus species, so I have planted it more as a curiosity than as a major player in the spring flower beds.  I scattered the bulbs at the edge of a few beds and in dry soil under some hickory trees where they won’t be smothered by more robust plants.  The only other things growing around them are some Cyclamen hederifolium that will be going dormant soon.

3. Trillium luteum

Trillium_luteum

Along the woodland path, a single T. luteum has persisted for the past seven years in soil that is really too dry and infertile for most woodland wildflowers.  I have a tendency to forget about spring ephemerals during the large portion of the year when they are invisible, so the little red cedar seedling makes a convenient marker when the trillium is dormant.

4.  Rhyncholaelia digbyana

R_digbyana

In this season–when the sun is rising higher in the sky, but the deciduous trees are still leafless–the greenhouse sees the most intense light of the year.  Not surprisingly, this is the blooming season of Rhyncholaelia digbyana, a central American species that requires intense light and hot, dry conditions for best growth.  My two plants are grown at the brightest end of the greenhouse in small terracotta pots with chunks of scoria and aliflor as the growing medium.

R. digbyana is one of the basic genetic building blocks of cattleya hybrids, and its fantastic, deeply incised labellum is the source of the large, frilly lip beloved of hybridizers.  The flowers also have a pleasant lemony fragrance.  Unfortunately, R. digbyana usually produces only one short-lived flower per growth, and those traits are also inherited.

5.  Sarcoglottis sceptrodes

Sarcoglottis

A terrestrial orchid from central America.  I think the flowers look like the heads of sauropod dinosaurs.

6.  Enanthleya Bob Gasko

enanthleya

This hybrid is (Guarianthe aurantiaca x Encyclia incumbens) x (Cattleya harpophylla x Cattleya neokautskyi), so three of its four grandparents have bright orange flowers.  Vegetatively, it is intermediate between a Guarianthe and an Encylia, with cigar-shaped pseudobulbs that flush red in bright light and two stiff leaves on each pseudobulb.

For more Six on Saturday, navigate to The Propagator.  See his participant’s guide if you want to post your own.

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Six on Saturday #20, February 3, 2018

It’s already Sunday across the Atlantic where the host of “Six on Saturday” lives, but it’s still Saturday evening here.   I guess it isn’t too late to participate.  And regardless of whether it’s Saturday or Sunday where you live, you can still head over to The Propagator’s blog to see his Six and links to those of other participants.

It’s still well below freezing most nights, but there are tentative signs of life in the garden…

1. Cyclamen coum

cyclamen_coum1

cyclamen_coum2

Cyclamen coum isn’t as vigorous and well adapted to our climate as C. hederifolium, but a couple of tiny plants are hanging on under the pines.  Every year, they bloom in the dead of winter, and every year I almost step on them.

2.  Helleborus niger (Christmas rose)

Helleborus_niger

The foliage of Helleborus niger has been flattened by the snow and cold, but at least it isn’t hiding the flowers on their very short stems.  Some people trim off the old leaves of hellebores just before they bloom.  That would certainly make the flowers of this species more visible, but I worry that removing leaves from a slow-growing evergreen species would be detrimental.

3. Lonicera fragrantissima (Winter honeysuckle)

Lonicera_fragrantissima

The flowers of Lonicera fragrantissima certainly aren’t spectacular, but the fragrance is absolutely wonderful.  I planted a row of the shrubs at the top of our driveway, at the northwestern edge of our property, so the prevailing west winds of winter spread the perfume down towards our front door.  I’d be quite proud of myself if it wasn’t completely fortuitous.  The direction of winter breezes was the furthest thing from my mind when I was deciding where to plant them.

L. fragrantissima is frequently found on lists of invasive plants, but luckily I very rarely see any fruit and have never found a volunteer seedling.  All of my plants are a single clone, and I wonder if they are not very self-compatible.

4.  Epidendrum stamfordianum

Epi_stamfordianum

In my greenhouse, this pretty little central American orchid is blooming for the first time.  It is still a fairly small seedling, so I expect to see longer inflorescence with more flowers in subsequent years.

5. Rauhia decora

rauhia_decora

This is the first year that my Rauhia decora bulb has produced two leaves instead of just one, so I am cautiously optimistic that it may be approaching blooming size.  If it doesn’t bloom this year, then maybe in 2019.

6.  Pachypodium brevicaule

pachy_brevicaule

I can see inflorescences starting on several of the spring-blooming Pachypodiums, but P. brevicaule is always the first to flower.

Three orchids

Some years, the first daffodils bloom about now, but this year almost everything in the garden is either dead or in deep dormancy.  For a little floral color, I have to rely on my greenhouse.

Here are three orchids with nothing much in common except that they bloom now.

1. Mormolyca ringens

Morm_ringens

This little orchid from Mexico and central America blooms pretty much all year round, with a single flower on each wiry inflorescence.  Like a surprising number of orchids, M. ringens is pollinated by pseudocopulation.  In other words, it induces naive (or desperate) male bees to mate with its flowers [1].  The labellum of the flower resembles the rear end of a small red-and-yellow bee, and it even produces a scent that mimics the pheromones of virgin queens [2].  Drones that attempt to mate with the flower transfer pollen to and from the overhanging yellow column.

2.  Brassia species (spider orchid)

brassia2

Brassia orchids also deceive their insect pollinators, but the mechanism would probably be better described as “pseudo-predation” rather than pseudocopulation.  Brassia flowers are pollinated by spider-hunter wasps which attack and repeatedly sting the labellum, apparently mistaking it for the body of a large spider [3].

brassia1

I think this is probably the Mexican/central American B. verrucosa, but I am not certain. It has been suggested that there are actually two different species circulating under that name [3], and in any case, Brassia species all look very similar to my non-expert eye.

3. Broughtonia Jamaica Jester (B. negrilensis x B. ortgesiana)

broughtonia

This is an artificial hybrid of two Broughtonia species, the Jamaican B. negrilensis and Cuban B. ortgesiana which was registered by Claude Hamilton, a well known grower and hybridizer of Caribbean orchid species.

broughtonia 2

References

1. Singer, R.B., Flach, A., Koehler, S., Marsaioli, A.J., and Do Carmo E. Amaral, M. (2004). Sexual mimcry in Mormolyca ringens (Lindl.) Schltr. (Orchidaceae: Maxillariinae).  Annals of Botany 93: 755-762.

2. Flach, A., Marsaioli, A.J., Singer, R.B., Do Carmo E. Amaral, M., Menezes, C., Kerr, W.E., Batista-Pereira, L.G., Correa, A.G. (2006)  Pollination by sexual mimicry in Mormolyca ringens: a floral chemistry that remarkably matches the pheromones of virgin queens of Scaptotrigona sp.  Journal of Chemical Ecology 32: 59-70.

3. Pupulin, F. and Bogarin, D. (2005) The genus Brassia in Costa Rica: A survey of four species and a new species. Orchids 74 : 202-207.

A neotropical blueberry

Macleania 3
Macleania species aff. smithiana (H.B.G. 89922)

No bonus points for guessing the pollinator of this plant.  It has hot pink tubular flowers of heavy, waxy substance.  It has to be pollinated by birds, right?  If I tell you that it’s from South America, then it’s obviously hummingbird-pollinated.

Macleania–a genus in the Ericaceae, the blueberry/rhododendron/heather family–is a plant geek’s delight.   Macleania species are found in central and South America, generally in high altitude cloud forest. Many are epiphytes that produce lignotubers, swollen roots or stem bases that store moisture and nutrients.  Their tubular flowers come in shades of bright orange, red, and pink, highlighted with green and yellow, and their berries are often sweet and edible.

The label of the plant illustrated above, Macleania sp. aff. smithiana, indicates that it may or may not be the species M. smithiana.  It generally fits the description of M. smithiana, except that its flowers are pink/yellow instead of orange-red/green.  Since plant descriptions are generally based on a limited range of specimens, it may turn out to be a color variant of M. smithiana.  Alternatively, it might be a closely related species.  The “aff.” (affinis) in the label reflects that uncertainty.  It came with an accession number from the Huntington Botanical Garden (HBG 89922), so there’s a chance I may be able to find out more someday.

I purchased this rooted cutting in autumn, 2016, because it was advertised as originating from lowland forest near Esmereldas, Ecuador.  Most Macleania species in cultivation are from higher elevation and are therefore less likely to tolerate our long hot summers.  So far, the plant has performed well, producing clean new growth and blooming for the first time this month.  I am growing it in a mix of permatill and long-fiber sphagnum moss, outside under shade-cloth in summer and in a cool corner of the greenhouse in winter.