The Crevice is “Woke”

The crevice garden has “woke” for spring, with early flowering plants in full gear. Here’s a shot of one small section, featuring Delospema dyeri and Iberis simplex (taurica). We hope you can visit in person for the second weekend of our spring open house, May 6 – 8, 2022.

A Little White Lying Groundcover

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.

Calanthe Love

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.

Next-gen ajugas

Here are images of three of the “next generation” ajuga cultivars, all selections of the Italian Ajuga tenorii. These in-ground photos were all taken at JLBG on April 1. These new ajugas don’t spread wildly or seed around like many of the older, more commonly grown offerings. We think they are pretty darn amazing! The top photo of Ajuga ‘Blueberry Muffin’ represents several plants, planted on 1′ centers. The second image is a single plant of Ajuga ‘Cordial Canary’, and the third is a single plant of Ajuga ‘Petite Parakeet’. These are actually non-staged images, unlike the highly staged, completely unrealistic, manufactured photos you often see in the Dutch-centric catalogs. Hardy from zone 4a to 9b.

Ajuga ‘Blueberry Muffin’
Ajuga ‘Cordial Canary’
Ajuga ‘Petite Parakeet’

Crazy Eddie’s Dunce Cap

In our cold frames, some plants will occasionally flower out of season, and that’s the case this week when one of our Orostachys ‘Crazy Eddie’ plants decided to flower out of season…fall is it’s normal time. The offseason timing won’t adversely affect the plant, and it did give us an unexpected photo moment. Because of the form of the flower, orostachys gained the common name, dunce caps, named after the pointed caps that poorly performing students were forced to wear. Of course, you’re probably showing your age if you knew what dunce caps were.

Streaked like a Comet

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.

Plant Imposters

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.

Aspidistra linearifolia

Weeping cast irons

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.

Aspidistra ebianensis ‘Flowing Fountains’

Ice n’ Roses Dilemma

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).

Helleborus x glandorfensis ‘Ice n’ Roses Pink’

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.

Helleborus x glandorfensis ‘Ice n’ Roses Red’

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?

Helleborus x glandorfensis ‘Ice n’ Roses White’

The Spectrum of Siblings

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.

Rohdea japonica ‘Stork Nest’
Rohdea japonica ‘Thin Man’
Rohdea japonica JLBG-091

Raising Rabieas

We have long loved small crevice-sized succulents, but have also killed far more than our share, due mostly to our wet, cold winters. The newest star in our trials is the South African, Rabiea albipuncta, a first cousin to the better known, Delosperma. We should mention, that new DNA research has actually suggested a name change to Nananthus vittatus would be more correct, so we’ll be re-tagging shortly.

This gift from Denver Botanic Garden plantsman extraordinaire, Panayoti Kelaidis, has thrived in the gardens since 2018. We actually tried this back in 2004, but our site simply didn’t drain well enough in winter. This image was taken here at JLBG on February 2 this year, which shows how insanely tolerant the flowers are of cold weather. We hope to make this available next year through Plant Delights Nursery. This gem forms a substantial caudex, and as such is highly prized by bonsai enthusiasts.

Rabiea albipuncta

Ruscus Crazy

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 hypoglossum
Ruscus 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.

Ichang Winter

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.

Asarum ichangense foliage
Asarum ichangense flowers

A Characias Cracker

For years, we struggled to grow the Mediterranean/Balkan native spurge, Euphorbia characias…until we discovered its secrets. First, it isn’t a long lived plant to begin with…in most cases 3-5 years is it, so you’ll need to plant it where it’s likely to reseed. That would be well-drained slopes that are either mulched or covered with gravel.

Secondly, after it flowers in spring with its stunning show of yellow flowers, remove most of the flower stalks as soon as flowering has finished, except those needed to produce new seedlings (the flowers are also great to use in floral arrangements). If not, the seed stalks use up energy causing the plant to decline much faster. We’ve now allowed this to seed throughout the slopes in front of our house, and here is the result…a smattering of 3′ tall x 3′ wide clumps, photo taken mid-winter.

Although this section of the garden, planted in compost-amended sandy loam is irrigated, we typically don’t recommend irrigation for this spurge without excellent drainage. You’ll also read on-line that Euphorbia characias doesn’t like hot, humid summers…another example of fake gardening news that just keeps getting repeated without any concern for the facts.

We’ve also found Euphorbia characias to grow well in part sun under large trees, which keeps the soil dry. The plants will never be as dense as they are in full sun, but they survive and flowers. There is really not anything else that gives you this evergreen blue color and form in the winter garden.

bloomin’ Ice n’ Roses

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.

Helleborus x glandorfensis ‘Ice n’ Roses Barolo’

Artist’s Palette in Winter

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.

Asarum hypogynum ‘Artist’s Palette’
Asarum hypogynum ‘Artist’s Palette’

A Major Minus

Asarum minus ‘Cupid’ is one of our heavily silver patterned selections of our native wild ginger. When cold weather arrives, the evergreen leaves take on a lovely purple cast. This is an excellent clonal selection we made in 1994 from a construction site, and one we hope to offer in the future though Plant Delights Nursery.

Lithophytes, epiphytes, tigers, and bears…oh my

Just out in the garden in early January and wanted to share photos of a few of our favorite evergreen ferns that would rather not be growing in the ground. In our garden, these are all growing within a few feet of each other.

Each of these ferns are epiphytes, which grow attached to a tree, or lithophytes, which grow attached to a rock. None of these ferns actually need soil to grow, since they get their food and water from the atmosphere and accumulated organic debris. Epiphytes, however, don’t get nutrients from their host plant…only physical support.

All epiphytic ferns thrive in hanging baskets, especially the spaghnum-lined type, since this most closely mimics their natural preferences. In our case, we are a bit colder than their native haunts, so for us, we force these ferns to reside in the ground since that gives them a bit more protection during severe winter temperatures. The key for epiphytes to survive in the ground is to have very loose, organic soils and always plant them on a steep slope.

Neolepisorus fortunei ‘Green Ribbons’ is our 2017 introduction of a Chinese native epiphytic fern.

Neolepisorus fortunei ‘Green Ribbons’

Pyrrosia lingua ‘Hiryu’ is also an epiphytic fern, native to Japan.

Pyrrosia lingua ‘Hiryu’

Lastly is Polypodium vulgare ‘Ulleung Island’. Instead of being an epiphyte, this evergreen fern is a lithophyte. Lithophytes are classified as either epilithic (growing across the rock surface) or endolithic (growing in cracks or crevices). Since we found this in the wild, growing across the surface of a giant rock, this fern is an epilithic lithophyte…say that three times fast. This is our 1997 collection from an island, far off the coast of South Korea.

We hope you’ll explore these unique ferns in your garden.

Polypodium vulgare ‘Ulleung Island’

Shishi

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.

Flowering Tractor Seat

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.

Lewis’s Ginger

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.

Mr. Butterfield’s Fern

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.

Hanoi Honey

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.

Aspidistra tonkinensis ‘Hanoi Honey’

Slim and Trim

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.

Rohdea japonica ‘Fukuju Kan’
Rohdea japonica ‘Feelin’ Groovy’
Rohdea japonica ‘Line Dance’

Red China

The dwarf groundcover Sedum tetractinum ‘Little China’ is superb throughout the growing season, but we particularly love when cold weather arrives and the olive green foliage turns to bright red in the sun…what a superb winter show. Hardiness is Zone 4a-8b.

Proud to be a Siberian

We don’t have many Siberian plants which thrive in the southeast US, so we get pretty excited when we find one that does. I was introduced to Microbiota decussata by the late JC Raulston, back in the mid 1970s, and actually still have one of my original plants that’s still alive. Many years later, a much improved form came to market under the name Microbiota decussata ‘Prides’.

Microbiota is a monotypic genus of conifer that has a textural appearance somewhere between a Juniper and a Selaginella.  In the wild, Microbiota can only be found in one small region of the Sikhote-Alin mountains, which is about 500 miles north of Vladovostok, Russia, where it occurs between 6,500′ and 7,000′ elevation.

Although Microbiota was officially discovered in 1921, and published in 1923, the Russian government, long-known for its secrecy, kept it completely under wraps until the early 1970s.

Unlike most junipers, which need sun to thrive, microbiota prefers shade to only part sun. Consequently, it you like this texture and don’t have full sun, this is the plant for you. For us, it matures at 18″ tall x 6′ wide.

Reineckea…the unknown cousin

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.

Fall Farfugiums

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 Senecio tussilagineus. It remained in the genus senecio until 1904, when it moved to the genus Ligularia, and became Ligularia tussilaginea. Here it remained until 1939, when it became Farfugium tussilagineum, 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.

Leaping Lepisorus

We love ferns of all types, but especially the single-leaf types. Our clump of the Chinese Lepisorus macrosphaerus really stands out in the fall and winter garden. In the wild, most lepisorus grow on rocks or tree trunks, but most we’ve grown have adapted well to growing in the soil. They tend to thrive better when growing on slopes, and in well-drained soils.

Lepisorus macrosphaerus

Green Eggs and ….pancakes?

Most everyone is familiar with Blue rug juniper…aka: Juniperus horizontalis ‘Wiltonii’, but few people know its dwarf cousin, Juniperus horizontalis ‘Pancake’. This amazing selection of the North American native groundcover is much slower growing, shorter, and with much finer textured foliage. Here is a recent photo of this amazing plant in the gardens at JLBG. Why is it that we never see Juniperus horizontalis touted for native plant gardens…hmmm?