Tuesday, April 8, 2008

Playing "Chicken" with Bletillas

It's that time of year again when I spend lots of time that I don't have covering and uncovering plants to protect them due to our unpredictable weather. Ironically, the most demanding in this regard are usually the Bletillas, a genus of hardy orchids from Asia which survive bone-chilling cold all winter, but whose foliage and flowers can be irreparably damaged by freezes in April. Last spring was a disaster in that regard, given our infamous Easter snowstorm.

Still, these are among my most treasured plants, especially some of the hybrids I was lucky enough to collect a few years ago, when ordering plants from the UK was less problematic. Some are more successful than others, and I always keep a plant or two of the rarer varieties in the cool greenhouse over the winter for insurance purposes. I have been growing Bletillas from seed over the past couple of years (see pics in the previous post on raising plants from seed), having discovered that the dust-like seed will germinate if mixed with fine sand and sprinkled over the surface of milled sphagnum in a clear plastic container; most other orchids require flasking under sterile conditions for seed propagation. I'm excited about the possibilities this opens up for hybridizing. Now all I need is more room in which to grow the young plants to maturity...

Other than a few articles online (notably one written several years ago by Clark T. Riley on orchidmall.com), and a chapter in the excellent book, Growing Hardy Perennial Orchids by William Mathis, there isn't much information available on growing this genus, so I've learned a lot by trial and error. One revelation came two years ago when I visited a nursery in Richmond and saw B. striata being sold as a marginal aquatic plant, seeming perfectly happy to sit with roots immersed in a deep pan of water; it appears that while they're in full growth during warm weather, overwatering isn't really an issue. Conversely, although the rhizomes can't take too much moisture when dormant, I did discover that storing the bulbs totally dry, as per pleiones, some zephyranthes, etc., is definitely not successful, either. At least partial sun (in combination with adequate moisture) seems to produce better growth and flowering than the usually recommended shade.

There are numerous varieties of B. striata, apparently the sturdiest of the tribe: this image shows both the straight species and the variant with a white stripe along the leaf edge.
To the right is the pure white cultivar (not a particularly good image); some forms have a bit of a purple flush on the tip of the column. There's also a pure white clone with variegated leaves, but the stripes are not very visible in this photograph:To the left is a variety called "Kuchibeni", also marketed as "First Kiss". It's as close as Bletilla striata comes to what is known in Cattleya breeding as a "semi-alba", white with a colored lip.

"Lips", the variety of B. striata pictured below, is unique in that its flowers are peloric, a word which describes their tendency to approach radial, as opposed to the usual bilateral, symmetry. It's this mutation which gave rise to "splash petal" cattleya breeding, and which brought about the varieties of Sinningia speciosa which are now known as florist's gloxinias. It's a strong grower, but has been shy about blooming. Most disappointing, however, is that the column is consistently malformed, producing neither viable pollen nor a functioning pistil, so the hybridization I envisioned appears unlikely.
I also grow a newer variety of striata called 'Murasaki Shikibu', the flowers of which are lavender with a much bluer cast than the other varieties. I made several crosses last summer using this cultivar, and the seeds have germinated, so I hope to eventually expand the color range. (Note: the image below is not my own, but I can't locate the original source.) It pains me to post the next two pictures, since the subjects have gone to "plant heaven", but B. formosana is an important species in terms of hybridizing, so shown here for visual comparison are both its alba and lavender forms:

Although B. formosana has not prospered under my care, its hybrid with striata, 'Yokohama', does very well. It shows sturdy, prolific growth which is intermediate between
its parent species and produces abundant pale purple blooms. I have numerous two year old F2 seedlings from this cross, originally obtained from Dr. Don Jacobs of Eco Gardens in Georgia; my hope is that some of them will exhibit the formosana phenotype while inheriting the hybrid vigor of 'Yokohama'.

The third species which is generally available is Bletilla ochracea (left), which is available in various shades of yellow and cream. It's not as strong a grower as striata, but holds its own, coming into growth and blooming later.
B. ochracea, in my view, is more important for its potential as a parent; 'Coritani' (left, B. ochracea x formosana) is a stronger grower than either parent, and often produces a second crop of flowers later in the season. 'Penway Sunset' (right, B. ochracea x szetchuanica - a species I've never even managed to flower), is a sturdy hybrid which produces more blooms per stem than any other in my collection.

'Penway Rainbow' (left), a complex hybrid (B. 'Yokohama', which is striata x formosana, crossed with B. ochracea), is, in my opinion, the best of the yellows so far, with strong coloring and a hardy, vigorous constitution. It should be noted that many of the grex names include the word "Penway" and were registered by the holder of the British National Collection, R. Evenden (This is as much of the name as I've located in my research so far).

Another very successful hybrid with ochracea is "Brigantes", the cross made using striata. I have three clones; one is nearly indistinguishable from striata, and another is a beautiful lavender with very rich lip coloration. The third called 'Moonlight', has striata 'alba' as a parent, and has been a much weaker grower than the others. I'm hoping to remake it (or something similar) this year using some of the stronger yellow hybrids listed above.

Two other species have been involved in hybridization, one of which, szetchuanica, I have attempted to grow. It apparently experiences a long period of dormancy, which shows up in its hybrids as a useful trait. This tendency also seems to make the species difficult to carry over the winter, due to its need for some moisture, but not too much. My experiences with B. szetchuanica have been similar to those I've had with Pleiones, in that there is grave danger of rot due to imperfect watering at the inception of growth in spring, and second chances are not given. It has produced some gardenworthy hybrids however, all of which show greater than average bud count per stem, with the flowers arrayed alternately, each facing more or less away from its predecessor.
Bletilla 'Penway Paris' (left) is striata x szetchuanica; 'Penway Dragon' (below) is formosana x szetchuanica; and 'Penway Starshine' (below, right), is 'Yokohama' x szetchuanica.

Rounding out the list of registered primary hybrids are those created using the elusive B. yunnanensis, which I've never seen offered for sale. I do have a plant purchased several years ago from a source in California which lists it as an unnamed species, "perhaps yunnanensis", but it's such a weak grower that it has yet to produce an inflorescence. Three of its hybrids, however, are growable, hardy plants, and one of these, 'Penway Rose' (left), is very distinctive in form and color, being a hybrid of B. ochracea with this species. 'Penway Princess' is yunnanensis by formosana, and 'Penway Imperial', a particularly strong grower which I have somehow neglected to photograph, is yunnanensis by striata.

Given all of their attributes as garden plants, it surprises me that Bletillas have not gained more popularity with gardeners in the temperate zone. Perhaps it has to do with the size of their blooms, or their limited blooming period, but their contribution to the garden continues through the fall with their pleated, arching sheaves of foliage, which is variegated in several varieties. My goal in seed propagation is not only to broaden the color spectrum of the available hybrids, but to produce F2 generations from the primary hybrids which combine the appearance of the more difficult and/or unavailable species with the sturdier constitution of Bletilla striata. I'm also attempting hybridization with Calopogon species, if for no other reason than the fact that I like the name given to this type of cross by the AOS - "Calopotilla".

In the time it's taken me to assemble this post, our usual frost-free date has passed (but only just), and I've uncovered the Bletillas, which are a little etiolated (they look like expensive white asparagus this morning), but appear none the worse for wear. I'm keeping my fingers crossed; in my book, emerging Bletilla pseudobulbs are right up there with Magnolia x soulangeana blooms as sure-fire harbingers of an April freeze!


Kentaki said...
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Jeff said...
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Kentaki said...

Sorry, but could you remove my name or message? I guess I left it unconsciously.

BTW, one of my friends sent me seeds of different Bletilla "varieties," which include red/orange Bletilla. I am going to sow them soon. Would there be a chance to exchange what we have if I could raise these seedling successfully? He also sent me seeds of Pleionilla (Pleione x Bletilla).

Jeff said...

Not a problem, Kentaki. I can't imagine my little seedlings ever being sturdy enough to survive mailing at this point, but it's always a possibility later. The seeds you're working with sound really interesting. I'm trying some Pleiones again this spring, but they've never done very well for me here - too hot and humid in the summer to suit them, I think.

Kentaki said...

Actually, I am not looking for your seedlings at this point. Maybe pollinia exchange? Or breeding materials?

I did read that you may be interested in creating Calopogon x Bletilla, but I also read the progeny of this cross were weak. I also wonder why their is no hybrid between Bletia or Spathoglottis. Supposedly, Arundina x Bletilla is hardy enough to survive in Tokyo, which is like Zone 8 or Zone 7b. Just a thought.

Pleionilla may be a good material to introduce "hardiness" of Bletilla into Pleione. I am not 100% convinced if plants my friends sent me a "real" hybrids. Will see.

AnnieAppleseeds said...

Hi Jeff,
Last year I waited to harvest seeds from the pods of my Bletilla and they had small dust like particles inside these spacious pods. Had I left them too long or are the seeds meant to be microscopic?
In any event, I just scattered them round the base of my existing bed of these. Now I cannot tell if they took or not, but I suspect not. The bed is wider but it gets slightly wider every year. How and when shall I divide these? They are happy beneath a crabapple tree in northern CA. Do they do best in shade or can they take full sun? Love your blog! Check out our website and would you be so kind to respond at my website address link? Thanks. www.AnnieAppleseeds.com We create custom tea, herb, or flower seed packets for business brand marketing and party favors in case you know of anyone wanting to "grow" their business or throw a large party.

AnnieAppleseeds said...
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Jeff said...

Hi Annie - wasn't able to reach your website; it was blocked by my virus software. Bletilla seeds, like those of all orchids, are very tiny and blow around like dust. I've never seen any germinate outside; all of mine have been germinated under fluorescent lights on moist, sterilized milled sphagnum moss. The whole pot remains enclosed inside a plastic bag for several months, then is gradually opened as the plants grow to a size at which they can be transplanted. It may be several years before they reach the size when they can be planted out.

I've grown the plants in sun or shade, but more blooms are produced in sun. More water is needed during the growing season if the plants are in sun, too.

Hope this helps!

AnnieAppleseeds said...

Thanks for your reply Jeff. If you live in the USA and you need seeds, I can mail them to you next time I harvest them. Growing these from seeds is more than I bargained for. Have never had anyone say my site is blocked by virus software before, hummm...
AnnieAppleseed@comcast.net is our email too. I assure you it is legit. Our positive feedback on eBay is proof of that. Our seller name is 123Appleseed in case you are curious about our products. Best of luck with your Bletilla. I really enjoy your blog. Annie

Tom Velardi said...

Jeff, that blue flowered plant is in fact the blue form called 'Soryu', not 'Murasaki Shikibu' and the photo is mine. I am an expat American living in Japan in the Fukuoka area. That particular plant is huge now, probably around 30 growths, most flowering size.

Ron said...

Jeff, would you please email me about Bletilla sources in the US?

I am in NJ...

Thank you for your help!



Anonymous said...
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Thomas Nelson Furniture Restoration said...

I am in Southside VA, and I am searching for seeds to plant Bletilla. Can you provide a source?

Erik said...

Hi Jeff, I know it's a year-old thread by now, but I just came across it now. So I hope you get this.

I grow bletilla and pleione in Dublin Ireland (equivalent to NW coast US most winters...zone around 8 or 9), both outdoors year round.Bletilla of course are easy, except that some summers don't give enough heat units to ripen the bulbs properly, and the following season there are few flowers as a result. Solved by keeping them in the plastic tent greenhouse all summer.

But it's the pleiones I wanted to talk about. Here, and also according to UK growers, being wet in the winter is not a problem so long as they stay cold. No idea why that is, but for the past six years they have been left out all winter through rain, frost, and snow, and manage just fine.

The summer treatment is what's really interesting. I grow them all on peat blocks (European peat is dense and cut into bricks as an old fashioned fuel, not like Canadian peat), which absorb moisture but never to a sodden extent.

In the summer, I stand all these pleione covered blocks in trays of water. They are sitting in full sun, with the bottom third of the blocks submerged. Root growth is prolific, and so is the growth (size and quantity) of new pseudobulbs. They love it. Maybe it is equivalent to monsoon conditions in Asia?

It might compensate for you against the heat of VA, to try some standing in water, semishade, good air flow. The bulbs are cheap if you get the "basic" species, so you could afford to experiment.

In winter, I hang the blocks on a wire fence. They are exposed to the elements, but drain fast, and get wind dried.

If your filters allow, you can see a picture of the pleione blocks on my Flickr site: http://bit.ly/faUc9n

Erik van Lennep

Jeff said...

Thanks Erik - I'm definitely envious of your gardening climate and intrigued by your method for growing Pleiones. If I can get my hands on a few bulbs, I may try again this summer, but the main US source for those retired a couple of years back and they've become all but impossible to find here. My gardening has been on the back burner for a couple of years now due to family and work issues, but I do appreciate your comments and interest. Happy New Year!

Kentaki said...

I was surprised some of my seedlings bloomed in 18 months since I started them from seeds. I have another batch that have been treated with a mutagen and oryzalin.

I also got a peloric form of Bletilla Brigantes and B. striata peloric form x 'Murasakishikibu'. Of course, the latter won't be likely bluish, but if I cross it back to 'Murasakishikibu', there maybe ones similar to C. intermedia coerulea aquinii. Will see. BTW, I don't know if you have 'Soryu', but I was told, progeny of this cultivar won't come true.

bqsore77 said...


i'm form belgium and also looking for several bletilla hybrids

in belgium they are difficult to find

please can someone help me with sending some seeds ?