Paphiopedilum Johanna Burkhardt

Paph_Johanna-Burkhardt

I have previously written about two fine old primary hybrids made with Paphiopedilum rothschildianum: the Victorian P. Lady Isobel and P. Saint Swithin. Here is a modern one, and it may well be the best.

Paphiopedilum Johanna Burkhardt is P. rothschildianum x P. adductum, and it was registered in 1994. My plant was made using P. adductum var. anitum as the pollen parent, and the results are spectacular. P. rothschildianum has contributed flower size, number, and overall form, while genes from the very dark P. adductum var. anitum have produced a dorsal sepal, petals, and pouch with dark reddish-brown markings on a yellow background. P. adductum var. anitum has also reduced the overall size of the plant, without affecting flower size; this plant has about half the leaf-span of my other P. rothschildianum hybrids, but its flowers are just as large, if not larger. A Google search for this grex will turn up pictures of better clones, many of them awarded, with huge, muscular-looking flowers and dorsal sepals that are almost black.

P. adductum var. anitum is sometimes considered a separate species, P. anitum, in which case this hybrid would be P. Wössner Black Wings (P. rothschildianum x P. anitum). From a horticultural point of view, there’s something to be said for distinguishing the dark plants made with P. adductum var anitum from those made with lighter colored P. adductum clones. However, the International Orchid Register lists P. Wössner Black Wings as a later synonym of P. Johanna Burkhardt, and both the Kew World Checklist of Selected Plant Families and a recent checklist of the genus Paphiopedilum (Koopowitz, H., 2018, Orchid Digest 82: 178-235) consider P. anitum to be a synonym of P. adductum.

Eight hybrids using P. Johanna Burkhardt as a parent have been registered, but none of the photos I have seen suggest that they are any better than–or even as good as–their parent. I’d go so far as to say that in this group of orchids, the primary hybrids are almost always better than complex hybrids. After more than 120 years, P. Lady Isobel and P. Saint Swithin are still well worth growing, and I suspect that the same will be true of P. Johanna Burkhardt in another century.

Paintbrush lily

Inflorescence of Scadoxus puniceus

This is exciting! After about six years in the ground, my Scadoxus puniceus has finally decided to flower. I was afraid that I wouldn’t get it to see it in full bloom: The day after I noticed a bud emerging from the mulch, the temperature dropped to 28 F (-2.2 C), so I surrounded it with bubble-wrap and covered it with a large plastic pot. That seemed to be sufficient insulation, because a couple of weeks later I have this beautiful orange inflorescence. The many small flowers are surrounded by petal-like spathes, giving it the appearance of a large single bloom.

Scadoxus puniceus is an African member of the Amaryllidaceae, the daffodil family, so it is not a true lily. Its range in the wild extends from Western Cape Province in South Africa northwards to Tanzania, with disjunct populations in Ethiopia [1}. Given its tropical and subtropical native habitat, it is somewhat surprising that it has done so well in my garden. It has survived temperatures as low as 5.5 F (-14.7 C) when buried under a thick layer of mulch, and despite its reported preference for a dry winter dormancy, it grows in clay that stays wet all winter long.

I suspect it took so long to flower because it is heavily shaded in summer by a large American beautyberry bush (Callicarpa americana). Last year, I planted a couple of young plants in sunnier spots. They survived the winter but are still too small to flower. Maybe next year.

Reference

1. Duncan, G., Jeppe, B., and Voight, L. (2016)  The Amaryllidaceae of Southern Africa, Umdaus Press, Pretoria, South Africa.

Giant Peruvian daffodil

Paramongaia1
Paramongaia weberbaueri

eBay can be a wonderful source for rare and unusual plants, but there’s always a chance you won’t get what you expect. I bought this plant in 2014, and it arrived as a small dormant bulb with no distinguishing characteristics. It could have been almost anything, and I had to wait 6 1/2 years to find out if I got an excellent deal on a very rare bulb, or paid way too much for a mislabeled Narcissus. In this case, I can breathe a sigh of relief, because the plant was as advertised.

Paramongaia weberbaueri is, despite its common name, not a daffodil. It is in the same family as daffodils, the Amaryllidaceae,, but while daffodils are native to the Mediterranean region, Paramongaia is from South America–specifically western Peru, where it grows in the rain shadow of the Andes. There are apparently two forms of the species, a high altitude form which grows and flowers in summer, and a winter-growing lowland form. My plant is obviously the winter-growing form. I keep it in a bright spot in the greenhouse year-round (minimum winter temperature 60 F, 15 C; summer maximum 93 F, 34 C). During winter I water at least once a week, or more frequently if the soil dries out. Then I leave it completely dry, no watering whatsoever, all summer long. Presumably, the humidity in the greenhouse is sufficient to keep the bulb from desiccating while dormant.

The flower bud developed relatively slowly for an Amaryllid and lasted just under a week in good condition. The fragrance was wonderful.

So far, my plant has shown no tendency to produce offsets. The anthers failed to produce pollen–or dried up prematurely, I’m not sure which. In any case, I was unable to self-pollinate the flower.

Paramongaia2
Paramongaia weberbaueri, whole plant with juvenile Homo sapiens to show scale.

Renanthera imschootiana

Ren_imschootiana1

Depending on how I do the math, I have been waiting to see these flowers for eight years, or just over twenty five years.  Back in the mid 1990s, when I first started growing orchids, I purchased a seedling of Renanthera imschootiana ‘Saigon’ x self to grow under fluorescent lights in my student apartment in Michigan.  Orchid growers will recognize that it was a poor choice for my growing area; Renanthera species and hybrids require high humidity and very bright light–up to full tropical sun.  After a few years, I came to the same realization and sold the plant to make room for something I had a chance of flowering.

Fast forward to about 2005.  I now lived in North Carolina and had a greenhouse where I could give large orchids much brighter light and higher humidity.  I still loved red flowers, and the very rare R. imschootiana has a certain mystique. I decided to try growing the species again

But I couldn’t find a plant to buy.  This isn’t uncommon if you go searching for one particular orchid.  There are about 28,000 orchid species and hundreds of thousands of registered hybrids, so only a tiny fraction are in commercial production at any time.  Someone flasks a batch of seedlings, and that species is available for sale until they run out.  Then, the species may be virtually unobtainable, unless you know a grower who will give you a division, until someone else produces a new batch of seedlings.

Finally, in 2012, I purchased a seedling of R. imschootiana ‘Newberry’ x ‘Saigon’ from Carter and Holmes Orchids.  That one of the parents of the new seedling was the same as the parent of my old seedling probably speaks to the small gene pool of cultivated plants in the U.S. (Carter and Holmes doesn’t seem to have plants for sale any more, but I see that seedlings are available from Santa Barbara Orchid Estate).

So, about the plant:  R. imschootiana is a relatively small species in terms of leaf-span, although it can grow tall with time.  It is basically a slow-motion vine, taking ten years to grow the distance that a honeysuckle vine could grow in a week, but it eventually grows long enough to need support.  The main stem occasionally branches, and the roots and inflorescences grow from leaf axils at random intervals.  My plant is potted in a 4″ terracotta pot filled with large chunks of scoria (red lava rock).  When it got top heavy, I put the 4″ pot in a 6″ pot, and roots have filled the space between the pots.  The vining stems are supported by several stiff wires.

Ren_imschootiana3

After a few years in my greenhouse, the plant sprouted a stem that resembled an inflorescence, but instead of flowers it produced a single terminal keiki (plantlet).  The next year, the same thing happened, and the year after.  Many of the Renanthera species and hybrids more common in cultivation are lowland tropicals that grow well in a warm greenhouse, but R. imschootiana is from higher elevation (Assam, northern Indochina, Yunnan) and is noted for tolerating winter temperatures near freezing. Suspecting that the plant was too comfortable with a minimum temperature of 60 F in my greenhouse, I left it outside during the autumn of 2018 until temperatures dropped to near freezing.  I then put the plant on the floor of the greenhouse near the door and reduced watering so that it stayed cool and dry for much of the winter.  Whenever the weather was dry and above freezing, I put it back outside again.  Result: nothing.  Last winter, I just left the plant on a bench in a sunny part of the greenhouse and watered it along with all the other orchids.  Result:  four inflorescences.

So, ~1995-2020 = 25 years.  2012-2020 = 8 years.  Either span is a long time to wait.  I just wish I knew what induced the plant to flower this year.

Ren_imschootiana2

Behria tenuiflora: cultural enigma

Behria tenuiflora

Generally, by the time I have had a plant for a couple of years, I am fairly sure of what it needs to grow and bloom successfully.  Either that, or I have killed it and am sure of what was not successful. Behria tenuiflora is currently flowering for the first time in my collection, and not only do I not have any idea what induced it to flower, I’m not really sure what caused it to grow.

B. tenuiflora is a small bulb native to the southern end of the Baja California peninsula.  It was once included in the onion family, Alliaceae, but more recently has been classified in the Themidaceae, a small family of bulbous plants from Mexico and the southern United States [1].  Its closest relative is the Mexican Bessera elegans (see entry 2 of Six on Saturday #8), which is commonly available from the big bulb vendors and seems relatively easy to grow as a potted plant in this climate.  On the basis of my success with Bessera elegans, I leapt at the chance to purchase a seed-grown corm of Behria tenuiflora from Telos Rare Bulbs in 2016.

Based on what I had read about the plant, I expected it to be a summer grower–its habitat supposedly receives most of its rain in the summer monsoon–and its growth in 2016 supported that supposition.  It started growing later than my Bessera plants and went dormant later, but it definitely grew in late summer.  However, it did not bloom that year.

In 2017, it didn’t sprout, and at the end of the summer I unpotted it, expecting to find it dead.  Instead, the corm seemed perfectly healthy, just dormant.  The same thing happened in 2018.  In winter 2018-2019, I tried giving it a few light waterings to see if it wanted to be a winter grower.  No, it didn’t.

This summer, I put it outside yet again.   Surprisingly, a single cylindrical leaf sprouted in July, and it has now rewarded me with its bright, candy-like flowers.  Judging by their shape and color, they are surely pollinated by hummingbirds.

I am not certain what caused it to grow and bloom this year.  My best guess–and this is only a guess–is that the growth is a response to moving it from a terracotta pot to a plastic pot this spring.  Behria tenuiflora comes from an arid environment with irregular rain, so I had assumed that it would grow best in soil that dried rapidly.  But perhaps it is adapted to remain dormant after intermittent showers and to grow only when significant rainfall occurs and the soil will likely remain moist long enough for the plant to complete its growth cycle.  The more constant moisture in a plastic pot might be what it needed in order to break dormancy.

I guess I’ll have to wait and see what happens next year.

Reference

Gándara, E., Sosa, V., and León De La Luz, J. (2009).  Morphological and Molecular evidence in the delimination of Behria and Bessera, two genera of the Milla complex (Themidaceae). Bol. Soc. Bot. Méx. 85: 113-124