Our mountain camellia (aka: Stewartia ovata) is in full flower this week at JLBG. Despite its reputation as being difficult to grow, our plant has reached 12′ tall after a decade in the ground. This native deciduous small tree can be found from Virginia south to Alabama, centered on the spine of the Appalachian mountains. Hardiness is Zone 5-8.
One of our Paeonia ostii seedlings flowered well for the first time this year, and turned out to be semi-double flower instead of the typical single flowers. We’ll continue to observe it in future years and make sure the trait is stable, but if so, this could be a lovely addition to the world of hardy tree peonies that tolerate heat as well as cold.
Few gardeners have probably grown the Taiwanese Rhododendron oldhamii, but this little-known species has become one of the most important azaleas in American horticulture. Here it is flowering in our garden in late spring. Then will be followed by a late summer/fall rebloom.
Rhododendron oldhamii was named for British plant explorer Richard Oldham (1837-1864). Here’s a fascinating summary of Oldham’s life/work. Despite dying at the young age of 27, Oldham made significant contributions to botany, including the rhododendron (azalea) named in his honor.
In the early 1980s, Louisiana nurseryman, Buddy Lee decided to see if the fall reblooming trait of Rhododendron oldhamii would transfer to its offspring. Indeed they did, and because of Richard Oldham his namesake azalea, and Buddy’s imagination, we now have an entire series of reblooming azaleas, known as the Encore azaleas.
Our anthropomorphic cat, Jasper decided this nearby Ligularia japonica would make a fine parasol substitute when siesta-time arrived on a recent bright sunny day..
Chances are pretty good that few US gardeners have grown molopospermum. We’ve long been fascinated with members of the Apiaceae family (think carrots, celery, Queen Anne’s lace, etc.). Not only are most members culinary/medicinal, but they are also great host and food plants for insects.
Several of the Apiaceae family members are great for garden design, because they possess an airy fern-like texture. One such plant that I’ve long been fascinated by is the monotypic Molopospermum peloponesiacum. Despite the specific epithet indicating that it’s native to the Peloponnesian peninsula (Greece), such is not the case. An error was made when Linnaeus named the plants, that has never been correct. Molopospermum is actually native to the Alps and Pyrenees, spanning from Spain through France and into Italy, where in grows in open woodlands.
We weren’t sure if it would survive our hot, humid summers, but after finally tracking down seed, we have several thriving plants in the garden from a 2018 planting. Although we haven’t had any flower yet, we await the 5′ tall spikes.
One of our favorite ferns is the Lady fern hybrid, Athyrium ‘Ocean’s Fury’. Created in Pittsboro, NC by plantsman Thurman Maness, this patented gem was offered for years through wholesale channels, but sales were not strong enough, so the sole producer discontinued it. So often, great patented plants suddenly become unavailable if sales don’t warrant.
In Europe, any grower can petition the PVR office to request permission to propagate such protected plants, but no such program exists in the US. Fortunately, Thurman has generously granted us permission to propagate his amazing introduction and make it available. That said, division is a very slow way to make ferns available, but since this hybrid between Athyrium filix-femina and Athyrium nipponicum is sterile, it’s our only option.
Looking good in the garden this week is the amazing fern, Dryopteris x australis. This rare fern is a US native…despite the confusing name, hailing from only a few scattered locations from Virginia west to Arkansas. In reality, the name “australis” means from the south. This splendid specimen grows in both sun and shade, and tolerates both wet and dry soils. Hardiness is Zone 5a-9b.
We often talk about the amazing group of hardy asparagus ferns, so here we go again with a few that are looking particularly great now.
The first image is our dwarf selection of Asparagus cochinchinensis ‘So Fine’. This is our new dwarf selection from our original collection from Korea’s Mt. Chuwang. Hardiness is Zone 4b-8b, at least.
Asparagus tenuifolius ‘Vodice’ has proven to be an amazing garden specimen with a tight compact habit. This is our collection from Vodice, Croatia. It’s amazing that this incredible species is completely absent from gardens. We have no idea about winter hardiness, but would expect Zone 5/6 at least.
The amazing Asparagus sprengeri ‘Graham’s Cracker’ just continues to amaze us. This dwarf selection of the hanging basket asparagus fern from NC plantsman Graham Ray, has been reliable for years in Zone 5b, without the benefit of mulch or any other protection. We find it a superb textural contrast for bolder foliaged perennials.
The lovely native witch hazel, Hamamelis virginiana ‘Little Prospect‘ with its variegated foliage, looks amazing even when it isn’t in flower. The leaves show no foliar burn in full sun and it is just as beautiful in part shade. Hardiness Zone: 3a to 8b.
Looking great in the JLBG gardens is the amazing Cyrtomium fortunei ‘China Ruffles’. This superb spore strain is from an original introduction by Michigan plantsman, Hans Hansen, who made the spore collection in 2003 in Sichuan, China. Hardiness is Zone 6-9.
We’ll certainly remember 2022 for many reasons, but a highlight is the first flowering of our Davidia involucrata ‘Sonoma’. This incredible tree was named for French missionary and naturalist, Armand “Pere” David (1826-1900), who first discovered the tree in its native China.
Like dogwoods, what we think of as flowers are actually bracts, the effect is that of the tree in flower is like a dogwood on steroids. Interesting, davidia is in the black gum family, Nyssaceae, and although this tree is not common, it has acquired the common name of dove tree.
We’ve learned a bit about what davidia likes, having killed five plants since first trying it in 2002. Full sun is not ideal, as is deep shade. Our original plant, which as been in the ground since 2002 has yet to flower. The plant of Davidia ‘Sonoma’, which flowered this year, was planted in 2014, and is thriving in light shade/part sun.
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.
The dwarf, glossy-leaf Chinese Polygonatum nodosum just oozes elegance.
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’
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 ‘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.
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.
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.
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.
Ever since I was a small kid, I’ve observed Zephyranthes atamasco (atamasco lily) in the wild, where they grow in swampy wooded lowlands. Atamasco lily is also one of many great nomenclatural muddles with regard to it’s correct spelling. When it was first named by Linneaus, back in 1753, it was assigned to genus amaryllis, so the specific epithet was spelled “atamasca”.
In his later work, Linneaus changed the spelling to “atamasco”, which corresponded to the Native American name for the bulb. It remained spelled with an “o” even after it was moved into the genus Zephyranthes in 1821. The problem is that, according to International Nomenclatural rules, the original spelling must take precedent. So, Zephyranthes atamasca is correct. Except…there is an exemption for name conservation, when correcting the name will cause confusion or economic harm. There is currently a well-supported move underfoot to conserve the long-used spelling “atamasco”. And you thought nomenclature was boring!
I’ve long marveled at the diversity within the species, and as an adult have been fortunate to be able to collect offset bulbs from some of the special forms I’ve found.
The top image is a very compact form that we’ve named Zephyranthes ”Milk Goblet’. Below that is one of our larger flowered forms from Alabama that we named Zephyranthes ‘Hugo’. Hugo has 5″ wide flowers in a species where 2.5-3″ wide is typical. Both of these are in full flower now at JLBG.
We’re just back from a quick outing to the Flower Hill Nature Preserve in Johnston County, NC…just a few miles from JLBG. This unique coastal plain site contains remnants of species more common in the NC mountains, nearly 5 hours west. The top of the bluff is a small stand of enormous Rhododendron catawbiense, while along the bottom of the hill is a bank of the deciduous Rhododendron canescens.
In the mid-slope area, we found Cypripedium acaule (pink ladyslipper orchid), just waiting to be photographed. Sadly, it’s one of the most difficult species to transplant, so just enjoy these in situ when you find them.
There were beautiful masses of the evergreen groundcover galax, growing on the eastern slope.
It was particularly great to see the Asarum vriginicum in full flower. True Asarum virginicum is rarely seen in cultivation, and the diversity of flower color was outstanding.
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.
Tromping through the woods near the nursery last week and ran across this beautiful example of devil’s urn fungus (Urnula craterium). The original type specimen from which it was named in 1822 was from North Carolina.
Arum are a fascinating genus of hardy aroids, known by most gardeners from a single southern European species, Arum italicum. The most popular cultivar of Arum italicum is Arum ‘Marmoratum’. The key to enjoying arums is to not let the seed drop everywhere, since you can get easily get over-arumed. Flowering season is now, followed by seed season. Each seedling has a different pattern from the original, so it’s a personal preference whether to remove seed or not.
Arum apulum is a little-know species that is rarely seen in cultivation, native only to a small region of Southern Italy. Our flowering plants in the garden now are from a wild collection made by a plant explorer friend.
Below is an interesting hybrid between Arum italicum (central to southern continental Europe) and Arum dioscorides (Mediterranean). Arum italicum has patterned leaves, but solid green flowers. Arum dioscoridis has solid green leaves and spotted flowers. The hybrid, Arum ‘Chui’ is an introduction from UK plantsman John Grimshaw. We added the notospecific (hybrid) name Arum x diotalicum. These hybrids have both spotted/speckled leaves and flowers.
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.
Here are a few buttery-colored plants flowering today in garden, starting with Arum creticum ‘Golden Torch’. This started as a small field division of a particularly large flowered selection from our 2010 expedition to Crete.
Paeonia mlokosewitschii is known for being un-pronouncable, so most folks refer to it as Molly the Witch peony. This is a particularly lovely butter yellow form from Ellen Hornig of the former Seneca Hill Perennials.
Trillium sp. nov. freemanii is a still unpublished new trillium species (hopefully soon), that we discovered in 1998. Normally red flowered, this is a rare yellow-flowered form.
We love all of our trout lilies, but Erythronium ‘Goldstrike’ is hard to beat. This is our named selection of Erythronium americanum ssp. harperi. Occurring from Tennessee south of Mississippi, this amazing form graces low woodlands in very early spring. This collection was made by our Plant records/taxonomist, Zac Hill in Alabama. Hardiness is Zone 6-9 at least.
Flowering at JLBG since early March is the little-known Jack-in-the-pulpit, Arisaema ilanense. This collection hails from Ilan (Yilan), in northeastern Taiwan, and for us is the very first arisaema to flower each winter, even when temperatures are still quite cold. The mature size is only 4-6″ in height, so this is one for a very special site in the rock garden. There are very few plants of this species in ex-situ conservation collections, so thanks to JCRA Director, Mark Weathington for sharing. Our specimen has been in the garden since 2016. Hardiness is unknown, but we’re guessing Zone 7b-9b.
Edgeworthia chrysantha ‘Snow Cream’ is a 2000 Juniper Level Botanic Garden/Plant Delights introduction that has proven to be one of our most popular introductions. We made the original selection from a group of seed-grown plants, imported from China by Canada’s Piroche Plants in the late 1990s. We were drawn to this seedling because of the particularly large flowers, and large leaves that reminded us of a plumeria. Let me be clear that all Edgeworthia chrysantha seedlings are nice, but there is certainly a significant difference between flower and leaf sizes of seed-grown plants.
Below are photos from our winter open nursery and garden days this year, where our garden specimens never cease to amaze visitors with both its sweetly scented flowers and amazing floral show. Sadly, no matter how many we propagate, it never seems to be enough to meet the demand. A more open site results in a much better floral show. Hardiness is Zone 7a – 10b.
What a lovely color echo we caught this week at JLBG when the tiger swallowtails were visiting Mertensia virginiana (Virginia Bluebells). Remember that botanical diversity results in more pollinators in the garden.
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.
Wednesday, March 23, 2022 is the NC State University Day of Giving…a time for those who want to support activities at NC State. In our case, that means the endowment we are building to preserve Juniper Level Botanic Gardens. If you care about ensuring the gardens remain intact for future generations, please consider making a contribution to the endowment. You can do so at this link to the University Endowment Fund for JLBG.
For those who are relatively new to the gardens, here is a link to a historical timeline of the JLBG garden development.
You can find out more about the mission and future of the gardens here
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.
It was great during our recent winter open house to see so many folks noticing the aucubas in the garden. Of course, they are hard to miss with our collection of over 140 different taxa. There are few evergreen plants better for year-round interest in dry shade than aucuba. Here is one of the most fascinating ones that’s in flower now in early March, Aucuba himalaica var. dolichophylla. This little-known, narrow-leaf species hails from 3,000′ elevation in several southern Chinese provinces. Winter hardiness Zone 7a-9b, and perhaps a bit colder.
Trillium cuneatum ‘Oconee Gold’ is a rare gold-flowered selection of the typically purple-flowered southeastern toadshade. We found our original plant of this in Oconee County, SC, and have propagated them from seed since that time. If we keep the yellow-flowered plants isolated from purple-flowering clones, we have more than 50% that reproduce with yellow flowers. The time from seed to flower is usually five years. Winter hardiness is Zone 5a-8b.
Podocarpus macrophyllus ‘Okina’ is looking lovely this winter. This Japanese selection has resided at the base of a large pine tree at JLBG since 2001. We love the white speckled foilage, which really shines in the winter months. Podocarpus macrophyllus is one of a short list of conifers that thrives in the shade of a woodland garden. Our 20 year old plant is now 6′ tall. Hardiness is Zone 7b-10b.
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.
Flowering now in the woodland garden is this rad little windflower, Anemone raddeana. This Asian native (China, Japan, Korea, and Russia) is a plant you’ll almost never see for sale. First, it flowers in the middle of winter when few people are thinking about gardening. Secondly, it’s ridiculously small, producing only a single white flower per stalk, which rises only a couple of inches from a slowly creeping rhizome. Third, it’s a spring ephemeral, meaning it will be dormant by the first of May. Finally, most people move through life too fast to even notice little gems like this. That said, if you like things like this, this is exactly the kind of thing you’ll really like. We certainly do!
Few people know the fascinating native shrub, Dirca palustris. It’s little wonder it gets overshadowed by showier members of its family, Thymelaeaceae, which includes the likes of Daphne and Edgeworthia. Our 6′ tall plant is flowering alongside a large edgeworthia, and rarely gets noticed by visitors.
Dirca palustris, the plant, is actually widespread across Eastern North America, with a range from Canada to Florida, where it thrives in slightly moist, acidic soils. It’s often known as leatherwood, due to its thick, but very pliable branches, which have been used by Native Americans for making rope as well as baskets.
There are three other less poorly known dirca species…if that’s possible. We grow the rare Dirca decipiens from Kansas/Arkansas, but have not yet tried D. occidentalis from California, or D. mexicana from Mexico.
The genus takes its name from the Dirce in Greek Mythology, who bit the big one while tied to the horns of a bull….a truly sordid story. The specific epithet “palustris”, lacks the fascinating story of the genus, but only means that the plant naturally lives in very wet sites. Winter hardiness is Zone 3-9.
Picea rubens (red spruce) is one of only 8 US native spruce species, and the only one whose natural ranges includes North Carolina. The entire range of red spruce starts in Nova Scotia and continues south to high elevations in the NC mountains. Genetic testing indicates that our red spruce evolved due to climate change during the Pleistocene (12,000 years to 2.5 million years ago), when it split off from Picea mariana (black spruce). Black spruce is now the only other nearby spruce, which currently resides from New Jersey north with a small population in Northern Kentucky.
Surprisingly, red spruce is virtually absent from piedmont gardens, probably due to the common wisdom that it doesn’t tolerated heat and humidity. As long as it’s given adequate amounts of Calcium (we aim for a pH of 6.5), it grows beautifully. Here is our 26 year old specimen, that didn’t get the memo that it’s shouldn’t grow here. Hardiness is Zone 3a-8a.
Red spruce wood is used to make high quality wood instruments like violins and acoustic guitars, but to avoid cutting down your lovely specimen, we recommend you stick with products that can be made from the foliage, like the infamous Red Spruce Beer.
When people think of trilliums, they usually think of the cold north, but states like Florida are also home to four species of trilliums which all thrive throughout the southeastern states. Here are two of the earliest species to flower in our garden.
The first is Trillium maculatum ‘Kanapaha Giant’ from Alachua County. This is consistently the earliest trillium to emerge and flower for us. This is followed close behind by Trillium underwoodii. Both of these are usually in flower by early February.
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.
Below is the same plant flowering in early April.
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.
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.
Below are more of the Ice n’ Roses snow roses flowering now in the gardens at JLBG. These amazing sterile hybrids were created in Germany by the Heuger plant breeding company. They have proven fabulous in our trials, but are still often difficult to find due to the screwy production cycle.
Because these snow roses, as Heuger calls them, are clonal and sterile, they can only be commercially produced by tissue culture, which is all done overseas. The non-rooted microplants are shipped in sterile containers to the US, where they are received at rooting stations (nurseries capable of putting roots on these microplants).
There are only three North American rooting stations used by Heuger, one in Canada, and one on each of the US coasts. Once the microplants have roots and have grown large enough, they are purchased by finish growers, who pot and grow them for 2-3 months before they are a saleable size.
For a finish grower or retail nursery to have plants available to sell in late winter or early spring, they would need to receive liners (small plants with roots) from the rooting stations in September/October. The problem is that these rooting stations usually get their unrooted microplants from overseas in fall, when their losses are less and the plants finish faster.
Consequently, these rooting stations only have plants available for the finish growers from February – April. This means that the finish grower and retailer will only have plants ready to sell at the beginning of summer, which is certainly not ideal unless you live in the northern tier of states or Canada.
The only option a finished grower has is to hold the plants through the summer and fall, to have them available in the late winter flowering season. This drives up the crop cost dramatically, since a nursery has an overhead cost per square foot per month of growing space. Until a change is dictated by the grower throughout the supply chain, it is unlikely that the supply will be able to keep up with the potential demand. Anyone think making plants available is easy?
Throughout the years, we’ve grown literally thousands…perhaps 10s of thousands of seedlings of the Japanese sacred lily, Rohdea japonica. Each one varies slightly, but we only save those at the far end of the bell curve. Here are three of our seedlings which well represent that dramatic variation at each end of the spectrum…a wide leaf form we named Rohdea ‘Stork Nest’ (15 yrs old), a very narrow leaf form we named Rohdea ‘Thin Man’ (16 years old), and a miniature that has yet to be named.
If you’ve visited JLBG, you know how much we love working with rocks, so we continue to find new areas to plant more. We’ve recently tackled two long overdue projects near the Mt. Michelle waterfall.
The first was re-working the Mt. Michelle watercourse we know as Mystic Creek (named after one of our late cats). When this was installed in 2003, we used concrete to form the water channel. Well, after 18 years, tree roots had their way with the concrete, which lost both the battle and the war.
After a fair amount of root excavation work, Jeremy and Nick installed a new rubber liner, with rocks along the edge. We’ll probably wait until spring to finish the replanting in order to avoid planting on top of something that was winter dormant. Below is the new rocked watercourse.
Phase 2 of the project was re-working an adjacent bed, where light levels had changed dramatically since it was installed in 1998. Originally a full sun bed, the shrubs on the west side have grown substantially, leaving us with a bed that only gets 3-4 hours of sun on one end, and a full shade area underneath the canopy.
Here, we raised the center of the bed, with more of Jeremy and Nick’s rock work, which was then filled with our on-site created compost. This created a visual barrier to much of the winding path that visitors use to get closer to the small plants, which are now tucked in the crevices.
One the back (west) side, Jeremy and Nick installed another small rock seating area, of which there are never enough.
There are a few more days of rock work to complete Phase 2, then we’ll start on Phase 3, which will rework the west face of Mt. Michelle, with more boulders to create additional planting pockets. We hope you’ll check out the progress at our upcoming winter open house.
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 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 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 x microglossum (below) is a natural hybrid between Ruscus hypophyllum and Ruscus hypoglossum…quite a tongue-full.
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.
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.
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.
Here’s a mid-winter shot of our front grotto, showing what that section looks like during the most trying time of year. We try to emphasize to those building new gardens to treat gardens just like rooms of your home. Each should have a floor, ceiling, walls, furniture both large and small, and decorations. In the garden, we also try to emphasize year round interest, which in our area includes a good selection of evergreens. Our Winter Open Nursery and Garden Days coming up in a few weeks is a great time to get ideas and inspiration for your own garden. Below is a “before” picture of the same area.
Below is the same shot when this section was begun in 1988.
The Helleborus x gladorfensis hybrids, known as the “Ice n’ Roses” series have begun with the opening of Helleborus ‘Ice n’ Roses Barolo’. This is the earlies flowering and darkest clone in the series…just a shade darker than H. ‘Ice n’ Roses Red’. These are sterile hybrids derived from crossed of Helleborus niger with Helleborus x hybridus. Winter hardiness is Zone 5a-8b.
Asarum hypogynum ‘Artist’s Palette’ is in full flower here at JLBG in late January. Despite being first published in 1915, this little-known species is very poorly represented in ex-situ plant collections worldwide. Our clone is a division from a wild plant we brought back from our 2008 botanical expedition to Taiwan. The foliage on this species is some of the largest in the entire genus. For us, Asarum hypogynum starts flowering in late summer and continues most of the winter. We are working to eventually be able to share this with other collectors. Hardiness is Zone 7b and warmer.
We love busting horticultural myths, and here’s our latest. Borinda fungosa is another of the wonderful clumping bamboos from China, which, according to bamboo authorities, will not tolerate either our winter temperatures or our summer heat and humidity. Well, darn!
Excuse us for sharing this photo from late January, but here is our 2010 planting of a seed grown plant, and of course, it’s easy to see how poorly it’s growing. That said, we know that it will die to the ground at single digits F, and then re-sprout the following spring. The lesson…don’t believe everything you hear or read.
Here’s an image taken this month of the wonderful Aucuba japonica ‘Limbata’. While most aucubas have yellow leaf specks, this old cultivar, first mentioned in historical literature in 1864, is sadly still quite unknown in gardens. That’s not too surprising, however, due to its slow production time as a commercial nursery crop. For dry shade in Zone 7a-9, this wonderful broadleaf evergreen is hard to beat.
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.
It’s hard to imagine a better plant in the fall/winter garden than the southeast native woodland perennial, Gentiana saponaria. Looking quite amazing in our garden throughout December is Zac’s collection from Rockford, Georgia. We hope you’re growing this amazing plant in your garden. Hardiness is Zone 6b-8b, at least.
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 evergreen holly fern in all it’s species and forms. Cyrtomium falcatum ‘Butterfieldii’ is looking absolutely stupendous in the garden this month. This easy to grow shade lover glistens all winter with its glossy foliage with fancy serrated edges. Hardiness is Zone 7a-8b.
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.
Anyone who has visited JLBG, knows we are huge fans of the Japanese sacred lily, Rohdea japonica. While the variegated forms are certainly showy, we also love the solid green varieties, especially the narrower leaf forms, so here are a few of our favorites. The top is Rohdea japonica ‘Fukuju Kan’, followed by Rohdea ‘Feelin’ Groovy’, and finally Rohdea ‘Line Dance’. All photos were taken in our gardens this week. For us, these amazing evergreen plants remain looking great all winter and the orange-red winter fruit are a bonus. In the garden, they function like evergreen hostas. The first two are what is known as dragon-ridge (crested) varieties. Hardiness is Zone 6b-9b.
We love fall and winter, when Woodwardia orientalis ‘Mama Mia’ starts producing baby ferns on the old foliage. Mama Mia can be propagated from the plantlets, but in our cold winter climate, the babies rarely mature unless taken indoors for the winter. The evergreen foliage of Woodwardia orientalis will show damage at about 10 degrees F and Zone 7b is the northern-most range of its cold hardiness.
We’ve been working on upgrading many of the temporary gates throughout the garden, our first few, which went in this year are all designed by NC sculptor Jim Gallucci, from photos we took in the JLBG Gardens. We all need more art in our gardens…Enjoy!
Sarcococca saligna is one of our favorite species of sweet box, but sadly one of the most tender. If winter temperatures drop below 10F, it dies to the ground, but has always resprouted. When we have mild winters, it becomes an extraordinary woodland garden specimen as is evidenced by this current photo.
One of our most cherished evergreens in the winter woodland garden is the narrow-leaf form of butchers broom, Ruscus aculeatus ‘Chenault’. Our plant came from the Elizabeth Lawrence Garden, and Elizabeth’s plant originated in France’s Chenault Nursery circa the 1960s. Our 20 year old plants are now 3′ tall x 4′ wide. Although they rarely fruit, they provided a unique texture compared to most other forms of the species.
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.<