Solomon’s Seals comprise several genera of woody perennials, but the common name is most commonly associated with the genus, Polygonatum in the Asparagus family. It seems hard to imagine, but the Asparagus family now includes many popular garden plants including its namesake Asaparagus, but also hosta, agave, liriope, ruscus, and yucca.
The genus Polygonatum is native through much of the world, although the center of distribution is in Asia. We’ve been collecting these amazing woodland perennials for years, and now have a collection of over 380 different taxa. Here are a few from this week in the garden.
Polygonatum mengtzense is a dwarf, rarely cultivated species from North Vietnam.
Polygonatum mengtzense BSWJ11691
The dwarf, glossy-leaf Chinese Polygonatum nodosum just oozes elegance.
Polygonatum nodosum
When you run out of species to grow, you start creating hybrids. This is our new selection of a cross of the giant Polygonatum martinii and the more compact, Polygonatum falcatum. We’ve named this clone Polygonatum x marcatum ‘Winsome Wonder’
Polygantum x marcatum ‘Wisome Wonder’
Polygonatum odoratum ‘Chanticleer’ is a superb, large-leaf form of the Asian Polygonatum odoratum that I spied at Chanticleer Gardens, and they kindly shared in 2006. Hopefully, we’ll finally have enough to share next year.
Polygonatum odoratum ‘Chanticleer’
Polygonatum odoratum ‘Angel Wings’ (aka: ‘Carlisle) is a superb form of Polygonatum odoratum from Massachusetts plantsman, Roy Herold. This gem grows in both half day sun as well as shade.
Over the last few weeks, I’ve been working on a plant survey of a local woodland area of about 30 acres. The low, moist areas are filled with Arisaema triphyllum, (Jack-in-the-pulpit) which is quite common in our area. The first image is what is typical for the species.
Arisaema triphyllum Wake County, NC
I’ve been studying patches of Jack-in-the-pulpit for well over 55 years, always looking for unusual leaf forms that showed any type of patterning. Until last month, I’d never found a single form with atypical foliage. That all changed with my first trip to this local site, where so far, I have found several dozen forms with silver leaf vein patterns. Up until now, there are only two pattern leaf forms of Arisaema triphyllum in cultivation, Arisaema ‘Mrs. French’ and Arisaema ‘Starburst’.
Each patterned leaf clone varies slightly as you would expect within a population including both green and purple stalk coloration.
Arisaema triphyllum silver veined clone Arisaema triphyllum silver veined clone with green stems Arisaema triphyllum silver veined clone with purple stems
While I’d never found any true variegation prior to this, I had found plenty of transient leaf patterning caused by Jack-in-the-pulpit rust (Uromyces ari triphylli). This site was no exception, with a number of plants showing the characteristic patterning. If you find these, turn the leaf upside down and you’ll see the small orange rust pustules.
While these may seem exciting, the pattern are not genetic and will disappear without the fungus. Fortunately, this rust can be cured by cutting off the top of the plant and discarding it where the spores can not spread via the wind. Infected plant should be fine, albeit smaller next year. The susceptibility of Arisaema triphyllum to jack-in-the-pulpit rust varies with genetics. Of the tens of thousands of plants I observed at the site, less than 10% were infected with the rust.
Arisaema triphyllum with rust induced pattern Arisaema triphyllum rust induced pattern on leaf back
False lily-of-the-valley (Speirantha gardenii) is one of our favorite early spring-flowering evergreen groundcovers for shade, but one that just hasn’t caught on with customers. Every time we put this back in production at Plant Delights, we wind up throwing out most of the crop. Perhaps one day, folks will realize what a gem this is. Hardiness is Zone 5b-8b.
We are just starting with the first wave of Cypripedium (ladyslipper orchids) in the garden this week. One of the earliest selections to put on a show is Cypripedium ‘Rascal’, an outstanding cross of Cypripedium kentuckiense and Cypripedium parviflorum var. parviflorum…all US natives.
Here is a clump of Calanthe ‘Takane’ in our garden in early April. This amazing and easy-to-grow terrestrial ground orchid forms a dazzling clump with age. This mass started as a single division in a 4″ pot, 17 years ago. Not only do they thrive in the ground, but in Japan, they are prized as container plants.
Calanthe ‘Takane’ is a group of hybrids between Calanthe sieboldii and Calanthes discolor, so each seedling is slightly different in flower color. The foliage remains evergreen during most winters for us, but when temperatures drop near 0 degrees F, the foliage will die back completely. Calanthes thrive best in light shade. Winter hardiness is Zone 7a-9a.
Here’s a fun combination this from the garden this week, where we combined two three-leafed plants together…a silver leaf Trillium cuneatum with the hardy purple-leaf shamrock, Oxalis triangularis. You can have all kind of fun making these little vignette combinations in your garden, using your school colors, or any other design scheme that suits your tastes.
If you’re a nursery, and you’d like to offer ferns, the plants at your disposal are somewhat limited. A large majority of ferns sold in America are still sadly dug from the wild. When you see a catalog listing primarily these ferns together…usually an very inexpensive prices, you can be pretty much assured they were dug from the wild: Osmunda regalis (royal fern), Osmunda cinnamomea (Cinnamon Fern), Polystichum acrostichoides (Christmas Fern), Matteuccia Matteuccia struthiopteris (Ostrich fern), Adiantum pedatum (Maidenhair fern), Athyrium filix-femina (lady fern), and Onoclea sensibilis (Sensitive Fern). These ferns are often sold bareroot, to save the nursery the expense of having to pot the collected plants, many of which are so large, they won’t fit in small containers.
The other majority of ferns in the market are produced by tissue culture, either by a couple of labs in Florida, one in Texas, and one in Holland. Without the amazing work of these labs, the fern selections available to homeowners would be limited to the wild collections. Even with their amazing work, these labs must focus on well-known ferns that sell in very large numbers.
While we make use of the lab offerings, we also made a commitment over 30 years ago to grow many of our own ferns from spores. Outside of a few small fern specialists, there are few nurseries who grow their own ferns from spores, since this is the most costly and time consuming option. The reason we do this is so that we can offer fern species and selected forms that are otherwise unavailable.
Below is a quick summary of how the process works. Fern spores (fern equivalents of seed) are collected through the summer, and are dried in paper envelopes until they separate from the foliage. They are then sown in pots with potting soil that is sterilized here, and then sealed in ziploc bags. The spore takes from 1 month to 6 months to germinate. Once the spores germinate, they are ready to have sex…a process that is reversed from more modern evolved flowering plants.
To assist the ferns have sex, we gently add water to the newly germinated sporelings, since ferns (other than desert ferns) only have sex while they are swimming. The water is swirled around to mimic the feel of a whirlpool, then the bags are then resealed, and put in the dark where they are subjected to a near constant montage of Barry White music.
Within a few weeks, tiny fern fronds begin to emerge. At this point, the ziploc bags are opened to allow the humidity to equalize with the ambient air. After another couple of weeks the pots are removed from the ziploc bags. If the spore were viable and cleaned well without contamination, and if germination was good, there will be up to several hundred plants per pot.
After a few weeks, the sporelings are transplanted into a cell pack flat. Here they grow out for another few months until they are ready to be planted into our 1 qt. pots, in which they will be sold. In all, it’s about an 18 month process, and a good bit of labor. We’re really quite passionate about our fern collection at JLBG, which the visiting British Fern Society declared one of the largest/most diverse in the world. We hope you find the results worthwhile.
Carex conica ‘Hime’ has been in horticultural commerce for many decades, and remains a superb woodland garden sedge. The evergreen species Carex conica is native throughout Japan, where it occurs in woodland conditions. This variegated selection that goes by an array of names such as ‘Snowline’ and ‘Marginata’, but Carex conica ‘Hime’, which translates to “princess” seems to the the correct cultivar name. The tight 10″ tall x 20″ wide clumps of narrow white-edged leaves are topped with this fascinating floral show for us in early March. In 35 years of growing this, we have yet to see a single garden seedling.
One of the fun reasons to grow plants from seed is that each seedling is different…unless you’re growing highly bred annuals. Most non-hybrid seedlings will be under the bell curve, meaning they all look and behave relatively similar. As plant collectors, we get excited when one appears that falls outside the bell curve. An example is our wild ginger selection, Asarum maximum ‘Floragasma’, which has both far more flowers than we typically see with the species, but it also flowers 2-3 weeks before our other clones. Winter hardiness is Zone 7b-9b.
We treasure any plant that makes a great woodland groundcover, and are particularly smitten with the ophiopgon (mondo grass) and liriope (monkey grass) selections. We currently grow over 120 different ophiopogon accesions including quite a number of wild collections, at JLBG…see what a touch of OCD does for you. We’ve grown Ophiopogon ‘Comet’ since 1997, and love it for its white striped foliage and well-behaved growth habit. Hardiness is Zone 7b-10b.
We’ll never be accused of being galanthophiles (folks who are hopelessly addicted to collecting galanthus cultivars), but we do love the genus, and are fascinated with these mostly winter-flowering bulbs. Here are a couple in full flower now at JLBG. These have a preference for slightly moist-to-average woodland conditions.
The first plant looks for all the world like a fine textured carex, but in fact, it’s an iris. Iris dabashanensis is a little-known species from China, that thrives for us in light shade, but will also take a few hours of early morning sun. Our plant is a Darrell Probst collection from Sichuan, China. Winter hardiness is Zone 5a -8a.
Iris dabashanensis
Below is the same plant flowering in early April.
Iris dabashanensis
The other plant growing nearby in our gardens that fools even the keenest plantsmen is this liriope look-alike. In fact, this is a cast iron plant, Aspidistra linearifolia. This demonstrates why those pesky taxonomic traits matter. In 2008 we introduced a selection with a lighter central stripe down the center of each leaf called A. linearifolia ‘Skinny Dippin’ which we will be offering again in 2023. Winter hardiness is Zone 7b and warmer.
Most gardeners know the genus aspidistra (cast iron plant) from one or two species, and if that’s the case, you probably only know those which hold their leaves vertically upright. There are equally as many species with pendant leaves, which provide a completely different form in the woodland garden. Here are two of those pendant-leaf species from the garden this week.
The first is Aspidistra sichuanensis, which is one of the larger growing species. A single clump can easily spread to 6′ in width in a couple of decades. This clump has topped out at 3.5′ in height.
Aspidistra sichuanensis
Below that is Aspidistra ebianensis ‘Flowing Fountains’. With narrower, wavier foliage, it makes a large clump, albeit slightly smaller than Aspidistra sichuanensis. Both plants are winter hardy from Zone 7b and south.
We love the evergreen ruscus in garden, but realize they are a plant that will never be found at most mainstream garden centers. A genus of only 6 currently recognized species, native from Europe into Eurasia, these horticultural oddities are so odd that they once qualified to have their own plant family, Ruscaceae.
Now, with improved DNA testing, they were found to actually be members of the Asparagus family. Exactly where within the Asparagus family is still an ongoing debate. Within the last decade, they were grouped with Nolina and Dasylirion, which to those of us who work with live plants, made no sense. Most likely, they will wind up in their own section, but as distant cousins to better know genera like Rohdea and Liriope.
Ruscus are great evergreen plants for dry shade, in regions where they are winter hardy, which is usually Zone 7b and south. Ruscus are unique in that they don’t produce leaves, but instead have leaf like structures known as cladodes, from which the tiny flowers emerge. All ruscus species have both separate male and female plants, although there are four hermaphroditic (bi-sexual) cultivars of Ruscus aculeatus in commerce, which produce the lovely red fruit without a mate.
The most common ruscus species in cultivation is Ruscus aculeatus, which has a wide range from Western Europe through the Caucuses. A handful of named cultivars of Ruscus aculeatus can be found in the gardens. Below is a photo this month of Ruscus ‘Sparkler’ a self-fruiting form, whose 2′ tall height is mid-way between Ruscus ‘Elizabeth Lawrence’ and Ruscus ‘Wheeler’.
Ruscus aculeatus ‘Sparkler’
Ruscus hypophyllum is a species, which ranges from Spain to Northern Africa, that’s rarely cultivated in the US. Other than the very tender Ruscus streptophyllus, this has proven to the be the next most tender species. Prior to trying these new forms of Ruscus hypophyllum, which were planted in early 2020, we had only grown a single clone, which had consistently died in our Zone 7b winters. These new plants are seedlings, grown from an Alan Galloway seed collection in Majorca, Spain.
Ruscus hypophyllum
Ruscus hypoglossum, which hails from Italy to Turkey, is a similar sounding species that we were fortunate to study in the wilds of Slovenia a few years ago, where it grew in mountainous open forests.
Ruscus hypoglossumRuscus hypoglossum flowers
Ruscus x microglossum (below) is a natural hybrid between Ruscus hypophyllum and Ruscus hypoglossum…quite a tongue-full.
Ruscus x microglossum
Ruscus colchicus is a species we fell in love with during a trip to Hillier’s Arboretum in 2005. Hailing from NW Turkey to the Western Caucuses, Ruscus colchicus is possibly the most elegant garden species. We are fortunate to have three different clones growing at JLBG, which we hope to one day have enough to share.
Ruscus colchicus
Voted least likely to be found in an ex-situ plant collection is Ruscus hyrcanus, a species, whose native range is from the Crimea into Iran. In appearance it somewhat resembles a dwarf, horizontal-growing version of Ruscus aculeatus. We are thrilled to have been able to offer this little-cultivated species in the past through Plant Delights.
Ruscus hyrcanus
We hope you’ll take notice of these great evergreens during your next visit to JLBG.
Another of the mid-winter flowering species of wild ginger is the Chinese Asarum ichangense. Here is a green leaf form of this easy-to-grow wild ginger in late January from the top. If you push aside the leaves, you’ll see the amazing floral show, hidden beneath. Winter hardiness in Zone 6b-8b, and possibly colder.
Rohdea japonica ‘Shishi’ is looking lovely in the woodland garden. Rohdea ‘Shishi’ is a dwarf Japanese selection of the evergreen sacred lily with leaves that curl downward creating an unusual bird nest like appearance. Winter hardiness is Zone 6b-8b.
We recently had someone inquire if we grew tractor seat plant, a common name I had not heard prior. After a brief pause, I figured few plants, other than our 2000 introduction, could possibly fit that name. Sure enough, a quick web search confirmed that Farfugium japoncium var. giganetum ‘Marco’ is indeed their target. While wandering through the garden this weekend, I found one clump still in flower, that somehow avoided damage from several nights at 27 degrees F.
To our knowledge, this giant form of Farfgium japonicum, native Japan’s southernmost Ryukyu Islands, was first brought to the US by plantsman Marco Stufano, who rationed out one plant per year for a NY Rare Plant Auction. When Marco was ready to retire from Wave Hill, he finally shared a piece with us, so we could get it mass propagated, hence we named the clone in his honor. To our knowledge, all tractor seat plants sold in the US came from Marco’s original plant.
This is the best fruit set we’ve ever seen on the Chinese Disporum longistylum ‘Green Giant’. We love this semi-evergreen Solomon’s Seal, that was collected and introduced years earlier by our friend, plant explorer Dan Hinkley. On the West Coast, this reaches 7′ tall, but here in the hot, humid southeast, we’ve never had ours exceed 3′ tall. Nevertheless, we’ll enjoy our great crop of cobalt blue fruit this winter.
One of several rare wild gingers we grow is Asarum lewisii, which has a small native range limited to central NC and adjacent Virginia. In the wild, the evergreen Asarum lewisii is quite unique in only producing a single leaf every few inches to over 1′ apart when growing in leaf duff. In the garden, however, leaves are much more dense as you can see in the photo from the JLBG gardens this week. It’s ashamed it doesn’t sell better when we offer it through Plant Delights.
We love the tardily deciduous Ctenitis subglandulosa ‘Hoshizaki’, which remains looking great in the garden as we pass the winter solstice. This truly elegant fern came to us from fern guru, Judith Jones, who got it from California fern guru, Barbara Jo Hoshizaki. The airy texture and ease of growth make this a fern we wouldn’t garden without. Sadly, we offered this Asian native (Bhutan through China) once through Plant Delights and very few people purchased one, so we had to discard the remaining crop…ouch! So very sorry you missed a true gem. Hardiness is Zone 7a-8b (guessing).
The cast iron plant, Aspidistra tonkinensis ‘Hanoi Honey’ has been looking quite stunning recently during its December flowering period. Unlike many cast iron plant that have reddish cinnamon flowers, this dazzler has large bright white flowers that are impossible to miss. Where it isn’t winter hardy, cast iron plants make fabulous, easy-to-grow house plants.
Most gardeners in mild winter climates are familiar with Liriope (monkey grass), and Ophiopogon (mondo grass), but almost no one is familiar with the third cousin, reineckea (false lilyturf). Like both better known cousins, reineckea is an evergreen groundcover, but unlike the others, here is our clump of Reineckea ‘Little Giant’ in full flower for Thanksgiving. Depending on your taxonomist, there is between 1-3 species in the genus. We’re certain of three and think there may be more. We have assembled a collection of nearly 30 wild collections and will be working with other researchers to sort out the taxonomy of this group.
One of our favorite fall woodland plants is a member of the Aster family, belonging to the genus farfugium. Farfugiums have long had a bit of an identity crisis, as they were originally named in 1767 by Linnaeus as Tussilago japonicum. In 1768, the same plant was also published as Arnica tussilaginea. Then, in 1784, it was moved to the genus, senecio, and became Senecio japonicus.
Later in 1891, it was renamed again, this time as Seneciotussilagineus. It remained in the genus senecio until 1904, when it moved to the genus Ligularia, and became Ligulariatussilaginea. Here it remained until 1939, when it became Farfugiumtussilagineum, but corrected the same year to match Linnaeus’s original epithet, resulting in Farfugium japonicum, which it remains today.
Below is our plant of the typical species, Farfugium japonicum in flower at JLBG this week. Through the decades, we have been collecting an array of other forms. Light open shade or a tiny bit of morning sun and average to slightly moist soils produce the best results.
Farfugium japonicum
Farfugium ‘Roundabout Fall’ is our selection of a hybrid with our Taiwanese collection Farfugium japonicum var. formosanum and the typical form. We like the smaller, thick, rounded leaf shape.
Farfugium japonicum ‘Roundabout Fall’
Farfugium ‘Jagged Edge’ is another upcoming JLBG/PDN introduction, scheduled for a 2023 release. It forms one of the larger clumps of any farfugium cultivars we’ve grown.
Farfugium japonicum ‘Jagged Edge’
Farfugium ‘Bashi Ogi’ is the only cultivar we know of Farfugium japoncium var. luchuense. This rare variety hails from Japan’s southern Ryuku Islands of Okinawa and Kagoshima. It differs in appearance by being a much smaller plant with leaves which are wider than tall. Here is our plant flowering now here at JLBG.
Farfugium japonicum ‘Bashi Ogi’
For 2022, Plant Delights will introduce JLBG’s first selection of Farfugium japonicum var. luchuense, that we’ve named Farfugium ‘Sweet Spot’. It’s a miniature seed selection from the above Farfugium ‘Bashi Ogi’, that only gets a few inches tall, so will make a great house plant, where it isn’t winter hardy.
Another genus of ferns that we just adore are the bamboo ferns of the genus coniogramme. We’ve grown these amazing gems for two decades, and after all that time are still in love. Although these woodland ferns are deciduous, they are tardily so, so they still look quite fresh into mid-November. Here are a couple of favorites, photographed this week.
At the top is the texturally fascinating Coniogramme intermedia ‘Shishi’ from Japan, and below this is our 2006 introduction of the Chinense native Coniogramme emeiensis ‘Golden Zebra’. We rate both of these as winter hardy from Zone 7b and warmer.
Flowering this week at JLBG is the little-known, but marvelous Liriope longipedicellata ‘Grape Fizz’, thanks to the exploits of plantsman Darrell Probst. We find this tightly clumping species much more interesting than the more formal Liriope muscari or the weedy, spreading Liriope spicata, and will tolerate full sun to shade. By the way, pedicles are stalk-like structures connecting one plant part to another….in this case the flower stalk to the flowers, hence the specific epithet longipedicellata (long pedicles).
Although some may have unpleasant memories of Wuhan after a year of pandemic conditions, let’s not forget that many incredible joys come from the same town. We are delighted to share the floral show of Iris japonica ‘Wuhan Angel’ this week…a plant originally shared by gardening friend Hayes Jackson, from his trip to Wuhan, China years earlier. This makes a superb, vigorous woodland groundcover in Zone 7b and warmer.