Gardening Unplugged - Hardy Orchids

Gardening Unplugged - Hardy Orchids

with Doug Ruhren

By Published July 17, 2023

Shop for Hardy Orchids at Plant Delights Nursery

Not all orchids are delicate tropical creatures destined to reside upon misted moss towers and cork bark. Some orchids are perfectly at home in the cold forests of Canada, and others are amazingly drought tolerant and easy to grow here in the South. Learn about hardy terrestrial orchids including Cypripedium, Bletilla, Callanthe, and Cremastra in this informative tour lead by our Senior Horticultural Garden Supervisor, Doug Ruhren.

Video Transcription:

Thanks for coming out for this. In any of these presentations, questions are very appropriate. The Orchid family is one of the largest families of flowering plants and you know obviously we're not going to cover the whole family and actually cover a very tiny part of the family with a focus just on hardy orchids. And primarily three that are the ones most readily available and the ones you're most readily to succeed with in the garden. And they are bletilla and we'll meet all these, cypripedium, which are the ladyslippers, one of the genera that have the common name of ladyslipper, and calanthe. We’ll meet these in the garden and on our way out to the Garden to see some examples if Greenhouse 5 is not too terribly busy, we might step in there because there's actually quite a few of the ladyslippers with flowers today. There’s a real pretty specimen out in the garden because the different species and hybrids don't all bloom at the same time. There were some that are now done blooming but there's one that's just perfect. Well, it was perfect yesterday, but I think it will still be fine. Okay well, we can get started.

All of the ladyslippers are on this far bench, and we can go in and you know just view them and then we'll go back out to the garden. The ladyslippers in the genus Cypripedium occur in North America. Quite a few species native to North America. Quite a few species are native to Asia. There are also a few that are native to Central America, Honduras, and I think Belize. In here and in the garden, we have some that are wild species and some that are man-made hybrids. And they all vary in their difficulty to grow. You know this is one that occurs locally. I've known of a plant, not a planting, but a wild population of this, a small one in Durham County, for 40 years that was still blooming this spring. This is the little yellow ladyslipper it's Cypripedium parviflorum. It used to be lumped with the European yellow ladyslipper which looks almost identical. But this is one of the wild ladyslippers that's quite easy to grow. You know the local ladyslipper that you’re most likely to see is the pink moccasin flower. Don't even think about transplanting it. You are not going to succeed. Nobody succeeds. Just leave it, enjoy it in the wild, and you know grow something like this or one of the hybrids which, with a reasonable amount of care, you should succeed with.

Cypripedium (Ladyslipper Orchid)

Cypripediums are woodland plants. I wouldn't put them in a really dark shady space place but a brightly shady place. Maybe with a few hours of sun but certainly not a full sun location. Now this is another wild species and I believe it occurs up in the Appalachian Mountains but not down in the Piedmont or the coastal plain. and this is one I would not recommend for this area unless you're like a real serious orchid grower because it really wants a colder climate. I remember being in I think Ohio in the spring, and you actually saw it on the edge of woodlands on the roadside. So, where it occurs naturally it's quite a vigorous thing, but it wouldn't succeed in this area. Its native range, I think, extends well up into Canada. And then the rest of these… let's see. Yeah, you can come on down.

The rest of the these are man-made hybrids. Somebody intentionally hybridizing the different species. And the catalog has a lot of really useful information and usually indicates whether one of these is a one that's easy to grow or more difficult to grow. But in general, the hybrids are fairly easy to grow. And these plants are at least seven years old which is why they are fairly pricey. But if you have the right conditions, they will get better every year. Every year they will tend to have more stems, therefore more flowers. Any questions on any of these guys?

Some of the other orchids we’ll talk about, well the calanthes are on that bench but we’ll see them out in the garden, and it’ll be quieter out in the garden. and then the bletillas are in Greenhouse 4 but we'll see some examples of them in the garden. We'll go back out this way.

Calanthe (Christmas Orchid)

Okay, a different genus, Calanthe. This is an example of the beautiful foliage of calanthes. The ladyslippers are all deciduous and I know we tend to think of deciduous in terms of woody plants but some herbaceous perennials plants that lack woody stems that live from year to year are evergreen. You know, like hellebores are evergreen, liriope is evergreen and the ladyslippers are deciduous but the calanthes are evergreen provided we don't go below 15 degrees. Now if the foliage gets burnt off it doesn't hurt the plant because this foliage only lives a year. It’s produced in the spring, and this was all this year's new foliage. And so last year's foliage would be dying off naturally anyway. So, if we have a cold winter and the foliage gets burnt off the plant is not affected by that at all. You know from a garden maintenance standpoint; you probably want to cut away the old foliage just because it looks a little untidy. So, the calanthes are quite easy to grow. Well, I should say Calanthe is a big genus, it's like somewhere between two and three hundred species, and the majority of which are tropical. But the ones that are winter hardy in this climate are quite easy to grow. and I enjoy their foliage year-round or at least until you know we have to cut it off in the winter, early spring. They’re mostly done blooming but a few more steps this way there's one that still has some flowers so you can start to get an idea of what they look like.

Q: I have a question.

A: Yes please.

Q: [Audience question]

A: Yeah, yeah, the question was, the ladyslippers we just looked at were in really deep pots and the question was - do they have a tap root. They do not have a tap root they have fairly thick fleshy roots. and the planting of the ladyslippers is a little bit more exacting than most other things. in the wild, the roots wouldn't be so much in the mineral soil but more in the duff layer, the rotted leaf litter on the surface of the soil. So, when you plant those ladyslippers you would dig a normal hole but then spread the roots out just below the surface of the soil and then always keep a good layer of rotting organic matter on top. It could be anything, it could be this hardwood mulch like we use, it could be you know the trees the leaves from the trees. But a lot of woodland plants end up with most of their roots in that duff layer rather than in the soil. So, when you took it take it out of that pot, you'd probably take all that potting mix often just you know spread the roots out. The calanthes and the bletillas you can just plant that like most other herbaceous perennials just in a regular soil okay.

I don't know if there's, there is probably a common name for calanthe, but you know the scientific name calanthe means beautiful flower. ‘Cala’ is from the Greek for beautiful and ‘anthe’ is flower. So, you know, sort of never worried about a common name for it. And this is a wild species calanthe. This is Calanthe discolor and discolor sounds like discolored, like something's discolored, but the ‘di’ just means two and you see it's two colored. sort of a red-brown and then with a white lip. Lydia is recording this, so she'll have proof that I removed the flower from the garden, but you know in the orchids, orchid flowers are highly modified. The outer whirls are actually sepals that look like petals. and then several of the petals become the lip and then the ladyslipper becomes the pouch. But a typical orchid has like three sepals and then I guess three sepals and then one true petal and then the other two petals are fused into the lip. And a really curious thing about most orchids in bud, the flower orientation is that way, but as it opens it turns downward. And that is characteristic of almost all orchids so the few orchids that don't do that are called resupinate. But these are really easy orchids. If you can grow hostas or most ferns, you can grow calanthe. and when a clump get gets thick you can dig it up and divide it and when we are looking at the bletilla I'll show you an extra little technique to increase your rate of reproduction. You see we haven't cleaned up last year's leaves but they're naturally just going, you know dying, because that's their life cycle. But they do have foliage through the winter, but the foliage only leaves for one year. There are several species we grow, Calanthe discolor. There’s also a lovely form that instead of red-brown sepals and petals they're lime green with the white lip, it’s real pretty. And then Calanthe sieboldii, named for a German with the family name of Siebold, it's a more robust plant. In bloom, it's about that height and the flowers are a bit bigger and they're bright yellow. Then there's a series of hybrids that are also really worth growing. Questions on any of them?

You see this is a full shade location, the sun's higher in the sky, there'll be brighter filtered light. It’s growing with a several different epimediums which, if you know the epimediums, you know they're definitely shade plants. A hosta and this primrose back here, Primula sieboldii, again the same German ‘Siebold’ collecting plants in Japan. Okay well, on to the ladyslipper that's so pretty. This is a little bit of a trek, but we'll take our time.

This is a big mass of a one cultivar of calanthe called ‘Golden Treasure’ and it was the brightest yellow without being gold, sort of like bright daffodil or forsythia yellow and about that tall in bloom and also fragrant. And it was early. That's one thing I should mention. The calanthes and the bletillas, which we'll see in a little while, both tend to come into growth real early in the year at a time of the year when we more often than not still have a frost. So, it is important to protect that new growth if we're going to go below freezing because the foliage, especially on the bletillas, if they get damaged, well it's going to be damaged the rest of the year. Because if frost cut off this foliage on either one of them, they're not going to put up new growth until next year. And you know, more often it doesn't get totally killed away but because we did protect it, this year's foliage looks nice and clean and will look good all summer long. you can see we again we didn't get last year's cut off and you can see it's starting to look shabby.

Q: How did you protect it?

A: Frost cloth. Yeah, lots of little bamboo stakes making little tents over things. It took us most of the day to go through all the gardens and protect things. Fortunately, well I'm knocking on wood because it's been crazy cool lately, fortunately we only had to do that once this winter. There are certainly winters when there are multiple late frosts.

Oh my, a bonus plant. Yeah, I didn't even see it yesterday when I was looking for the ladyslippers.

Here's a plant I didn't know we had to see today and here's the label way up here. This is an orchid. You know the whole spike might not look much like an orchid but, again Lidia will have the incriminating evidence that I've removed a flower. Let me put this label there. It’s a Cremastra appendiculata. so, something's an appendage or something. But I think if you sort of spread the petaloids you see that does start to look a bit like an orchid. Did you see it? and I think this species is Asian but it's a close ally… do you know our native woodland orchid putty root?

Audience: Yes

Yeah, a close relative of putty root. See, the foliage is much like putty root, pleated leaf but without the white stripes of putty root. But putty root is fairly common in woodlands around here. not as common as the spotted crane fly orchid. These flowers remind me more of a super showy spotted crane fly in their sort of translucent tan. Well, that was the treat. I didn't know we even had that to see today. This is… a few steps on we have the ladyslipper that's perfect right now but, and this one is Cypripedium ‘Rascal’. It’s a hybrid and you can see it did a good job of blooming. it's become a nice big clump. I don't know if this is one that's currently in production, but this is what I would expect out of some of the more robust hybrids. I love these sepals that spiral like that. You see that in other ladyslippers and other genera like the tropical paphiopedilums from Asia. I think the foliage… you see the foliage on the cypripedium is much like the calanthe foliage but instead of rising right from the crown of the plant its up on these stems. Again, you know a full shade area.

That’s South so the sun will probably be a little bit brighter later on in the day. but we'll go and look at this next cypripedium, it's kentuckiense. Anyone guess where that occurs?

Audience: Kentucky?

Yeah, whenever you see the e-n-s-e ending of a word it indicates ‘from’. You know, like Chinenses, Raleighenses.

But Cypripedium kentuckiense does occur in a wider area than just Kentucky. And it's one that's easy to grow. and it's done something that they'll do when they're growing robustly, it can have more than one flower on a scape. It’s a great beauty and it's big and showy. That's… I don't currently have a garden of my own but that's one I would definitely grow in a shade garden. So handsome.

Here's some… yeah this is Calanthe sieboldii and it's well past its peak, but you see it's a nice bright yellow. That ‘Golden Treasure’, the hybrid over there, is twice as bright a yellow as this but sieboldii is a big showy thing. You can see the scape, that's maybe almost a foot tall.

Bletilla (Urn Orchid)

Now when people are starting up with hardy orchids it's often this one they start with. It’s also the one that'll show up in almost any garden center. The other ones are more something you find in a specialty nursery. But this is a bletilla. The genus Bletilla is small, there are only five species. This is Bletilla striata, probably referring to the striations in the leaf. This is a location where it's not in the sun all day, but it does have some hours of sun and we have found that even though they will grow well, they will grow all right, they'll survive in a full shade area, they actually will flower a lot more with several hours of sun. Bletilla striata is a spring bloomer, it's almost done now.

This one has… I think this is the cultivar ‘Yokohama’. No, I don't see the label right now, but it has a slight white margin to it. There are other cultivars with much more variegation, 'Gotemba Stripes' is about half white half green stripes. The bletillas I'm real excited about are some of the other species and the hybrids because they're just starting to bloom now but they will bloom for months. some of them will bloom all summer and there are quite a few listed in the catalog. and whereas this is the typical height of Bletilla striata in bloom the things like ochracea, which means becoming yellow, or formosana, eventually the scape will be three sometimes almost four feet tall. So those are really worthwhile because you'll get months of bloom out of them. and there's a bunch of hybrids between them and they come in a wider range of color but Bletilla striata, this is the typical color. It can also be white or white with the purple lip, but the hybrids can be yellow and other colors as well. So, they're really those are really exciting ones partly because they bloom for so long.

How to Propogate Bletilla Orchids

Now, you could dig this plant up and divide it into individual stems but the way they have a rhizome underground that's jointed. In the orchid world it's referred to as the pseudobulbs. It’s not technically a true bulb. Let me step into the sunlight. Do you see this rounded part here? It’s about the size of a nickel or something. Well, when you dig these up, you'll have the lead bulb, which is this year's growth, and like a whole series of these pseudobulbs. sort of like an atta bead. well, this crowd probably knew atta beads, I don't know if young people know what atta beads are. I had two older sisters and of course my mom and their atta beads. but you could just divide a clump like this into individual stems with a long piece of rhizome but if you separate these pseudobulbs into separate pieces, and that's what was done here, each one of those will put up new growth. Yeah, so when you when you dig the bletilla up and you divide it into these separate pseudobulbs, each one of those will put up new growth. whereas in nature they're just hanging out until they're needed, and they might not ever be needed. and each one of these represents one year so that was last year's, that was two years ago, that was three years ago. Eventually they die of old age probably but they're just the backup reserve if something happened to the lead plant. So, when we divide them, we're essentially creating that situation where they're now needed, and they will put up new growth and you can do the same thing with the calanthes. where when you dig them up, you'll have these probably not quite as pronounced but instead of just dividing it so you have the stem with foliage, you can divide those older parts that don't have any foliage now because they're several years old. and that way when you divide them you can produce that many more plants.

Does that make any sense? Okay, yeah well, and it's like a lot of things with rhizomes like cannas and ginger lilies and stuff like that… I know I always thought you needed that lead. You needed this new stem. But actually, when I did a little potting demonstration, I had this overgrown pot of a ginger lily and I wanted to show how a rhizome is an underground stem. So, there's buds on it and when I chop that into maybe like two-inch pieces, it was actually the back pieces, not the one with the lead to put up the most shoots. Because the lead piece is just going to put up one shoot but, on something like a ginger or a canna, the part of the rhizome without that lead… all those buds along the rhizome are going to grow. So, whereas the lead tended to just continue growing, at that point the back parts put up multiple stems. So, when you're propagating, plants want to grow. so even when you chop them up, generally each piece is going to grow.

Orchids for Bog Gardens - Calopogon, Spiranthes

These are bletillas at the edge of the bog. They don't need a wet spot. They like moisture but just average moisture will also suit them well. They’re very adaptable to soil conditions. I'd avoid soggy, but anything from average moisture to moist. They wouldn't thrive in a dry spot. But in the bog, there's another orchid that's quite easy to grow. If you have a bog, if you like growing pitcher plants and stuff, or… there are more pitcher plants over here. The little grass pink calopogon is quite easy. If you're doing well with pitcher plants, then you have the right conditions for calopogon. There are also several ladies’ tresses which are spiranthes. The one that's been sold as ‘Chad's Ford’ is real vigorous. It doesn't bloom until maybe September, October but spikes of little white flowers. And spiranthes means spiral flower because the flowers on some of them are arranged sort of in a spiral up the spike. But there's a little spring blooming one that is also easy to grow.

That's about all I have to talk about it with orchids but I'm happy to entertain questions or anything. In a cold climate like cold and relative to the tropics, where so many orchids are native, in a cold climate like this there are basically no epiphytic orchids that survive our winter. And the epiphytes are the orchids that grow up on the limbs of trees and stuff. There is one that you can encounter down on the coast. It's a dendrobium and we do have a plant in the… you see those yellow foliage dawn redwoods, tallest tree in the distance, there's one on one of those trees but it's not something I would expect to succeed long term in a cold climate like that. So that orchids that survive our winters reliably are all terrestrial ones. Ones that grow down in the dirt. Questions on any of that?

You know, start off with bletillas and calanthes and, as I said, if you can grow hostas and stuff, you have the right conditions for them. If you feel a little bit more adventurous then try some of the ladyslippers. All right, well thank you very much. I appreciate you coming.

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