This terrestrial orchid has a confused and confusing nomenclatural history (see wikipedia), but it is a beautiful and relatively easy subject for the warm greenhouse or, possibly, a sunny windowsill.
Cynorkis angustipetala is from Madagascar and is a member of the subtribe Habenariinae, which also includes our native Platanthera orchids:
Platanthera ciliaris (yellow fringed orchid) flowering beside a road in Pender County, North Carolina. The overall morphology of the inflorescence and individual flowers is similar to that of C. angustipetala, but the highly fringed labellum gives a different impression.
In common with most of the tropical Habenariinae, C. angustipetala requires a dry winter dormancy when the foliage completely dies away, and the plant consists of a sausage-shaped tuber buried in the potting mix. C. angustifolia is one of the earliest of this group to break dormancy, and it will often start growing before I begin watering in the spring. My plants are currently blooming, while their relatives Habenaria rhodocheila and Pecteilis hawkesiana have yet to reveal whether they survived this year’s dormancy.
Potting mix can either be long fibered sphagnum or (my favorite) a 50/50 mix of sphagnum peat moss and perlite. Beware of perlite that has added fertilizer, because most terrestrial orchids react poorly to over-fertilization. In case any manufacturers read this: Hey! Stop putting fertilizer in perlite! The whole point of perlite is that it is inert.
Keep the mix constantly moist from early April until the foliage starts to yellow, probably in September or October, and do not water at all over the winter. If you are concerned about accidentally watering the pot (or over-drying the tuber in low humidity), you can seal the pot in a ziploc bag. Store the bag indoors in a dark place, because direct sunlight will cook the enclosed tubers.
Notice the whitish nectar spurs at the back of the C. angustipetala flowers that indicate pollination by sphinx moths or butterflies. The P. ciliaris shown above also has long spurs and is pollinated by butterflies.
The high contrast makes it difficult to see, but the lizard in the foreground is a mature male in his blue-bellied breeding colors. I’m not sure if the other is a female or an immature male, so this could be an amorous encounter or an aggressive one. Either way, they were too intent on each other to pay any attention to the giant human pointing an iphone camera at them.
Spring has really gathered steam over the past week, and for the first time in a couple of months, I had to select from among a wide array of flowers for this Six on Saturday.
This week, I’ll start in the greenhouse and then move outside.
1. Phalaenopsis mannii
The range of this small Phalaenopsis species extends from Assam to Vietnam and southern China. In common with some other Phal species, you should never cut the inflorescences when the spring/summer flowering season is finished. The old inflorescences will remain green through the winter and will produce new flower buds the next year. At the same time, new inflorescences will sprout, so as the plant gets older you’ll have more and more flowers each year.
2. Vireya hybrids (two for one)
Vireyas are a group of Rhododendron species from the old-world tropics, with the greatest diversity New Guinea, Borneo, Sulawesi, Sumatra, and the Philippines. The majority of species are from high elevation, so they prefer mild temperatures and do not appreciate the warm summer nights in North Carolina. In the USA, most vireya growers are on the west coast and Hawaii.
I have had long-term success with a few heat-tolerant vireyas whose ancestors come from lower elevations They do not tolerate frost, so in North Carolina they are definitely greenhouse plants. I’ve been growing these two plants since 2004.
Rhododendron jasminiflorum x (viriosum x jasminiflorum). The pink color is a mix of the white R. jasminiflorum and red R. viriosum, but the long, tubular flower shape is all R. jasminiflorum. This plant came from the late Bill Moyles, a well known vireya grower and hybridizer from Oakland, CA.This complex hybrid with peachy flowers is another Bill Moyles cross. It is Rhododendron (Felinda x (aurigeranum x Dr. Hermann Sleumer)) x javanicum. R. Felinda is ((phaeopeplum x viriosum) x leucogigas), and R. Dr. Hermann Sleumer is (phaeopeplum x zoelleri).
3. Ornithogalum dubium
Ornithogalum dubium is commonly sold by supermarkets and hardware stores as a throw-away flowering plant in late winter. Most people will probably treat them like cut flowers and toss the pot when the foliage starts to yellow. To keep the plants for another year, store the dormant bulbs dry and warm (or even hot) over the summer. Occasionally, bulbs will fail to sprout in autumn. As long as they remain firm, give them occasional water through the winter and then another hot dry summer. Often, they will sprout after the second dormancy. I have maintained these for five years, so there’s definitely no need to buy a new pot full every year.
And now, outside for the remaining three plants this week…
4. Tulipa clusiana var. chrysantha
Tulipa clusiana is reputed to be the best perennial tulip for the southeast. I first saw them blooming in Coker Arboretum at the University of North Carolina and was thrilled to find that they are very inexpensive from internet bulb vendors.
T. clusiana var. chrysantha flowers open in mid-morning and close back into tight buds in late afternoon. Although they have been flowering all week, I have seen only the orange buds when leaving the house and returning from work. Today was the first time I saw the bright yellow open flowers.
5. Saruma henryi
The fuzzy stems of Saruma henryi are just starting to emerge from the mulch, and the first flower is still wrinkled. S. henryi is related to Asarum, hence its genus name. Saruma is an anagram of Asarum. Those crazy botanists…
6. Scilla peruviana
Despite the name, Scilla peruviana is from the Mediterranean–Portugal, Spain, and southern Italy–not South America. The large bulbs produce their leaves in autumn, remain green all winter, and flower in spring. When I planted the bulbs last autumn, I wasn’t sure if they would survive outside, but they tolerated 3.2 F (-16 C) with only minor damage to the leaf tips.
To see what’s growing in gardens all around the world, head to The Propagator for his Six on Saturday and links to those of other garden bloggers.
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)
Last autumn, I planted some bulbs of Tulipaclusianavar. chrysantha and Tulipasylvestris. T.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
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
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
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
A terrestrial orchid from central America. I think the flowers look like the heads of sauropod dinosaurs.
6. Enanthleya Bob Gasko
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.
