One of my OCD exercises is keeping a list of desiderata plants for the garden, which I’ve either seen or heard about, and want to try. At this point, the list is closing in on a ridiculous 3,000 items. Some desiderata we find in less than a year, while others may grace the list for decades. One plant that had been on my list for about 20 years was Asphodelus acaulis…a fascinating stalkless species of asphodelus (most have tall stalks) from Northern Africa. Try as I might, I had been unsuccessful in tracking this down from any of my usual rock garden plant sources. It wasn’t until a 2018 plant shopping trip to the UK, that I finally found my grail plant in Bob Brown’s amazing Cotswold Garden Flowers. Now, going into its’ third season, it has settled in admirably, starting in late winter with its months long floral display of cupped light pink flowers nestled in the rain-lily like glossy green foliage. It is our hope to one day share this more widely…once we figure out the best propagation method.
Spirea thunbergii ‘Ogon’ is one of our favorite garden shrubs for its’ golden summer foliage, but we also adore it for it’s late winter/early spring floral show. Here it is at JLBG this week before the golden foliage emerges. You can see why it’s known by the common name, Bridal wreath spirea.
Looking lovely this week is the winter flowering anise, Illicium anisatum. This clone is Illicium anisatum ‘Murasaki no Sato’, which has creamy-centered leaves and new purple growth that’s just scrumptious. The winter floral show is also truly spectacular! This is first cousin to the tender Chinese anise, Illicium verum, whose pods are used medicinally. Illicium anisatum, however, is best used only ornamentally, since it’s fruit are toxic when consumed.
We’ve made several hellebore posts, which are hard not to do, since they put on such a great winter show in the shade garden. Here are some of our selections of the fertile Helleborus x hybridus from the garden this week. If you made it to our winter open house, you were able to see these in person. If not, this is the best we can do until next winter, when we hope you’ll add us to your travel calendar.
Helleborus x hybridus is a mixed group from a wide range of parents including Helleborus orientalis, viridis, atrorubens, purpurescens, torquatus, and probably others. The flower color of each seedling varies based on what other colored hellebore is growing nearby in combination with the genes of it’s past lineages. In the wild, most flowers from the hellebore species listed above are pendulous, since upright or outright flowers often doesn’t bode well for successful fruit set in snowy winter climates. Through the years, breeders have made incredible progress raising the faces of the flowers, and in other cases simply colorizing the petal exterior on drooping forms. We salute the amazing hellebore breeders who keep pushing the limits of what we thought possible.
One of our most popular introductions is Edgeworthia ‘Snow Cream’…a plant we first selected back in 1995…long before more than a handful of gardeners had even heard of the Chinese native genus.
The late JC Raulston grew a plant, known then as Edgeworthia papyrifera, just outside of the arboretum lath house back in the early 1990s, when I was Curator of the Shade House. It was a fascinating plant that I remember watching each winter as the tight white buds burst into yellow flowers. There was little detectable floral fragrance, the plant never exceeded 3.5′ in height, and it suffered mightily in cold NC winters. I was still entranced by the plant and propagated several and planted them around the NC State Fairgrounds, where I worked full time.
An interesting back story is that a population of Edgeworthia papyrifera was discovered along Wolf Creek in Rabun County, Georgia back in 1971. Author Wilbur Duncan and other native plant researchers were shocked and puzzled to find this new plant growing in the wild until it was later determined to be escapees, probably circuitously from an earlier 1903 introduction by the USDA..
In June 1995, I was visiting plantsman Roger Gossler at his family nursery, Gossler Farms, in Oregon. Roger had just received a shipment of edgeworthia from Piroche Plants in Canada. Since I had tried in vain to track down Edgeworthia chrysantha, I was thrilled at my luck in finally finding it. Going through their batch of seed-grown plants, I chose one that had the largest foliage and best form, which we eventually named E. ‘Snow Cream’.
For those who don’t know the Piroche Plants story, let me share. Back in the early 1990s, Canadian nurseryman/plantsman, Pierre Piroche was able to do what no one else had been able to manage and import quite a large number of very rare, commercially unobtainable plants, both woody and perennial from China. The story goes that Piroche first established a nursery in Bhutan that was able to import plants directly from China and then ship them on to Canada. Keen plant collectors around the country scooped up these gems until the Chinese import program sadly ended a couple of years later. Without his work, who knows if and when these superb forms of Edgeworthia chrysantha would have reached the US. A plantsman’s salute is in order for Pierre Piroche.
Edgeworthia taxonomy continues to be a moving target. The long known name Edgeworthia papyrifera was shot down when DNA studies showed that it was simply the diploid form of the triploid, and earlier published Edgeworthia chrysantha. Later, researchers dug up the yet earlier published name, Edgeworthia tomentosa (formerly Magnolia tomentosa)…a name which other researchers noted, is invalid since it was not correctly published.
Some folks have tried the orange flowered edgeworthia (‘Akebono’) that shows up in the market from time to time. Sadly, it’s the non-fragrant diploid form that has very little winter hardiness. We gave up on this in the mid-1990s after killing it our prerequisite three times. I am excited to share that a new orange-flowered form of the hardy fragrant form is finally poised to hit the market in the next few years.
Below are a few shots of Edgeworthia ‘Snow Cream’ at JLBG this week in it’s full blaze of glory. The daphne-like fragrance is akin to walking by a department store fragrance counter. Because of our consistently cool winter, flowering this year is about 2-3 weeks behind normal. We have found that edgeworthia grows equally as well in light shade or part sun…as long as the soil is well drained. Mature size seems to be in the 7-8′ range. To quote the late Paul Harvery…”Now you know the rest of the story.”
After showing many of the hybrid hellebores, here’s where they started. Flowering now at JLBG is one of our Balkan collections of the stunning Helleborus multifidus ssp. hercegovinus, which we grow for the foliage. This clump was started from a single division of a special plant we found in Montenegro…just after we crossed the border from Bosnia. The small green flowers are typical for the species. This is a slow-growing, summer-dormant species, which is why your rarely see it offered. If these are growin from garden seed, you get all kinds of hybrids, but almost never any with the stunning foliage of the true species.
If you’ve never read any of our plant expedition logs, here is a link to our Balkan travels where this gem was found.
Flowering now in the winter garden at JLBG is the winter-flowering dogwood, Cornus mas ‘Golden Glory’…also known as Cornelian Cherry. We’re not sure why this isn’t more widely used, since it’s quite easy to grow. Perhaps people don’t venture into garden centers enough in the winter.
One of several breakthroughs in lenten rose breeding has been the development of the Helleborus x glandorfensis hybrids by the breeders at Germany’s Heuger hellebores. In the town of Glandorf, near the border with Netherlands, these amazing crosses of Helleborus x hybridus with Helleborus x ericsmithii (niger x lividus x argutifolius) were developed. While there are several H. x glandorfensis clones entering the market now, the first two were H. ‘Ice n Roses Red’ and ‘Ice n Roses White’, which you can see below. The special traits of the series are large, outfacing flowers, sterility, and extremely dark black-green foliage. We look forward to bring more of these excellent hybrids to markets as our trials dictate.
Another recent dramatic improvement in hybrid lenten roses started at the small mom/pop nursery in England, RD plants. Here, Rodney David and Lynda Windsor created the first known hybrids of Hellleborus x ballardiae (niger x lividus) and Helleborus x hybridus. These revolutionary hybrids, previously thought impossible, are now known as Helleborus x iburgensis. They combine stunningly beautiful marbled foliage (from the H. lividus parent), with outfacing flowers (due to both H. lividus and H. niger), with a wide range of flower colors (due to Helleborus x hybridus). Because of the wide range of species used to create these gems, they have been effectively neutered so that no seedlings will be occurring in your garden. Below are a few from our gardens this winter.
Many clonal plants we grow today are propagated by tissue culture…also known as micropropagation. In most cases, this involves taking tiny cuttings and growing them in a test tube filled with a goey algae product known as agar. Tissue culture allows many rare plants to be produced quickly and often inexpensively, which is great when it comes to making plants available far and wide. When vegatatively propagating plants through more conventional “macro” methods, it’s usually easy to notice when a mutation occurs. That’s not always the case in micropropagation since the plants are much smaller and don’t flower until they are grown out after leaving the lab. This is why daylily tissue culture has been disastrous. All kinds of floral mutation occur in the lab, only to be noticed years later after the plants are sold and grown out in home gardens.
All of the hellebores clones are micropropagated and so far, we have found almost no floral mutations…until this week. Below is a micropropagated double-flowered clone of the Christmas rose, Helleborus niger ‘Snow Frills’. The top image is the correct plant with two rows of petals. The bottom is a mutation we found in the garden in which the second row of petals is mutated. Honestly, we like the mutation better. As a plant producer, however, we don’t know what form we will receive in our next batch of plants from the lab, but that’s simply the nature of the process.