Siberian Summer

Looking great in the garden despite our high temperatures is the Siberian native, Microbiota decussata. While the species typically struggles in our climate, the cultivar ‘Prides’ has been outstanding. Microbiota is essentially a groundcover juniper replacement for shade. For us, it matures with a 4′ wide spread, after 10 years. We have found that it does best in areas that stay slightly on the dry side, and in soils that are well-drained. There really isn’t another evergreen shrub that gives you the same texture in the woodland garden.

Microbiota decussata ‘Prides’

Garden Shots

Here’s an early June shot from the garden. The conifer in front left is Picea abies ‘Glauca Pendula Oxtail’. The weeping conifer in the distance is Cupressus glabra ‘Raywood’s Weeping’. The bright shrub in the distance is Ligustrum lucidum ‘Marble Magic’. Delve more into the world of woody ornamentals during the upcoming Southeastern Plant Symposium and Rare Plant Auction, June 16-17, 2023, hosted by JLBG and JCRA. Register now for in person or online attendance.

Plants, Plants, and more Plants – Southeastern Plant Symposium

Just over a month remains before the 2023 Southeastern Plant Symposium kicks off in Raleigh, NC. This joint symposium between the JC Raulston Arboretum and Juniper Level Botanic Garden will be held on June 16, 17 at Raleigh’s North Raleigh Hilton Hotel.

We’ve got thirteen of the world’s top speakers, as our 2023 symposium focuses on the coolest woody plants on the planet. You’ll find the schedule and speakers here, where you can also register. The rare plant auction now has a worldwide following, since quite a few of the plants simply aren’t commercially available anywhere, or in some cases are very new to the trade. We hope you’ll join us for a chance to hear and meet other passionate plant people and learn about trees and shrubs.

Symposium attendees will also be able to visit both Juniper Level Botanic Garden and the JC Raulston Arboretum before and after the symposium. The lovely folks at Ball Horticulture are also funding 10 college students to attend the symposium. You can apply on line here. We hope to see you there!

Van Hoey Who?

Platycladus orientalis ‘Van Hoey Smith’ is looking absolutely fabulous in our garden this winter. This fascinating selection of Oriental arborvitae, Platycladus orientalis was named after the late Dutch conifer guru, Dick van Hoey Smith (1921-2010), by an American nurseryman, who reportedly received these cuttings, unlabeled, from Dick. Some conifer folks think this is actually an old cultivar, Platycladus orientalis ‘Aureovariegata’. I understand this is not a good performer in climates with low humidity, but it sure likes it here in NC. Winter hardiness is Zone 5b-9b.

So, who is Van Hoey Smith? Born, James Richard Pennington van Hoey Smith, Dick’s family started the famed Trompenberg Arboretum in Holland, which Dick later ran from 1950 until he handed over the reins to his successor Gert Fortgens, in 1996. If you haven’t visited, I highly recommend a visit for any keen plant lover.

Dick was a founder of the International Dendrology Society, a membership society of the worlds keenest woody plant aficionados. He also wrote/photographed several reference books including Maples of the World, Conifers, and Rhododendron Portraits. He was awarded the worlds’ top horticultural prizes, including the Doorenbos Medal from the Dutch Dendrological Association and the Veitch Memorial Medal from the Royal Horticultural Society.

Platycladus orientalis ‘Van Hoey Smith’

Pinus in the Garden: Smaller is better

Here are a couple of dwarf pines in garden that are looking particularly great in mid-winter.

The first is PInus strobus ‘Mini Twists’ is a dwarf seed-grown selection of our native white pine that matures at 6′ tall x 4′ wide. This is a 2005 introduction from Vermont conifer specialist, Greg Williams. Good drainage is a key to success with white pines in our hot, humid climate. Hardiness is Zone 3a-8a.

Pinus strobus ‘Mini Twists’

Below is Pinus thunbergii ‘Thunderhead’, a 1987 introduction of a selected seedling of Japanese black pine from Angelica Nurseries of Maryland. In 10 years, it reportedly will reach 15′ in height x 20′ in width. Although it’s known commercially as Pinus ‘Thunderhead’, that cultivar name was actually used six years prior for a different pine, and according to International nomenclatural rules, can only be used once per genus, so the correct name would become Pinus ‘Angelica’s Thunderhead’. Hardiness is Zone 6a-8b.

Pinus thunbergii ‘Thunderhead’

A Little Bit of Norway

Looking great in the garden now is a dwarf witches broom selection of Norway spruce, Picea abies ‘Hereny’. Discovered by Hungary’s Józsa Miklós, and first published in 2010, it reportedly matures at 2′ tall in 20 years. Our 4 year old specimen has already reached that size, so we expect our warm summers will make it a much larger plant here.

Picea abies ‘Hereny’

Jurrasic Park Thujopsis

We’ve long been a fan of the central Japan native conifer, Thujopsis dolobrata, which we’ve grown for decades. For those, who aren’t students of the Latin language, the ending -opsis, means “looks like”. When Thujopsis was formally named in 1894 by Franz von Siebold and Joseph Zuccarini, they chose a name that could be translated to “looks like the American genus, Thuja”.

On a 2012 trip to Joann Currier’s former Unique Plant Nursery in NC, we noticed a plant of Thujopsis that looked unlike any we’d seen. Since the genus only has a single species, the variant was either a mutation or odd seedling. The very thick, plastic-like foliage on this selection gives the appearance of a ploidy mutation (extra chromosomes).

The cutting they shared was rooted, and subsequently went in the ground here in 2013. A decade later, our plant is pictured below this month, topping out at 10′ in height. Joann originally got the plant from Randy Plante at Greener Visions Nursery, who got it from NC conifer nurseryman Geoff Driscoll, who got it from someone “up north”. That’s where the trail goes cold. We’ve shared cuttings with several NC nursery folks, in the hopes this amazing selection becomes more commercially available in the future.

Thujopsis dolobrata ‘Jurrasic Park’

A Lumpy Pancake

I was just admiring our specimen of the East Coast native, Thuja occidentalis ‘Concessarini’ today. I find this a fascinating plant in the garden, sadly never promoted by those who claim to extoll the virtues of native plants.

Our oldest specimen below is now 10 years old and measures 3′ tall x 6′ wide…quite a bit larger than it’s introducer claims it to be at 1′ tall x 2′ wide. If you dig deeper, you’ll see that the plant patent application shows they only measured a three year old plant, and have never bothered to update the mature size in their marketing or on their tags. It shows how little many plant introducers think of the end consumer, when they set them up for failure by promoting these fake mature sizes. Commercially, it is marketed under the fake trade name of Pancake arborvitae. That’s one seriously lumpy pancake.

This juvenile-foliage sport of Thuja ‘Linesville’ was discovered by nurseryman, Gabriel Cessarini. We think it’s pretty cool, just allow enough room in the garden. Winter hardiness is Zone 3a-8b.

Thuja occidentalis 'Concessarini' or Pancake arborvitae
Thuja occidentalis ‘Concessarini’

A Mound of Mitama

Cryptomeria is a monotypic genus (only one species) of conifer, native to Japan. Despite many reports that it hails from China, DNA has shown that these were brought from Japan and planted over 1000 years ago.

For over 40 years, we have been fascinated with the genus and have worked to collect as many cultivars as possible, currently 49 different ones in the garden. One of our long-time favorites is Cryptomeria japonica ‘Mitama’, an old Japanese dwarf selection that’s sold under the name ‘Globosa Nana’. Without any clipping, these retain a slightly informal green meatball shape, maturing at 6′ tall x 10′ wide. Below is our garden plant this week. Hardiness zone 5a to 9b.

An unpruned specimen of Cryptomeria japonica 'Mitama', commonly sold under the name 'Globosa Nana'.
Cryptomeria japonica ‘Mitama’

Uncommonly Common

Juniperus communis is a common landscape juniper with a wide natural distribution…one of the widest of any woody plant in the entire world.

In the North American part of its range, it’s widespread throughout the Western US, and across the northern tier of the country all the way to Maine. East of the Mississippi River, however, it’s virtually not-existent south of the Great Lakes.

Patrick McMillan had been telling us about a population he rediscovered from an earlier Henry William Ravenel (1814-1887) documentation of a single clone growing naturally in Aiken, South Carolina. Last week, we made the 4 hour drive to visit this ancient living fossil. Here is all that remains, growing in an amazing nature park, known as Hitchcock Woods, where it grows surrounded by a forest of Kalmia (mountain laurel).

We have this propagated and growing at JLBG, and hopefully in the future, when our plants get larger, we can share these amazing genetics with a wider audience.

Juniperus communis 'Hitchcock Woods'
Juniperus communis ‘Hitchcock Woods’

Gold Dragon

The false yew, Cephalotaxus harringtonia ‘Gold Dragon’ is looking particularly lovely during the fall season here at JLBG. This is one of our six year old specimens. We find that half day sun seems to bring out the best color without foliar burn. Hardiness is Zone 6a-9b.

Cephalotaxus harringtonia Gold Dragon looking great during the fall
Cephalotaxus harringtonia ‘Gold Dragon’

Red Velvet White Cedar

Chamaecyparis ‘Red Velvet’ is a juvenile-leaved selection of our native white cedar, Chamaecyparis thyoides, discovered and introduced by Florida’s Blue River Nursery. This recent introduction looks similar to the 1960s introduction, Chamaecyparis ‘Rubicon’, except that ‘Rubicon’ dies in the garden on a bad day, and on a good day looks like death would help it. Chamaecyparis ‘Red Velvet’, on the other hand, is a superb garden plant.

Chamaecyparis thyoides Red Velvet, Red Velvet White Cedar, a superb garden plant
Chamaecyparis thyoides ‘Red Velvet’

So, why is this the case? Well, there are two distinct forms of this US coastal native wetland species, Chamaecyparis thyoides. Some botanists recognize the southern ecotypes as a separate species, while other make no distinction. We agree with those who recognize the southern plants as a subspecies,.Chamaecyparis thyoides ssp. henryae, which has a natural distribution centered in the Florida panhandle, and is dramatically easier to grow in the garden. Chamaecyparis thyoides ssp. thyoides, which ranges from Maine to Georgia, is much more difficult to grow in most garden conditions.

Because white cedar is native to cool fresh-water wetlands, very few cultivars perform fine in average to moist garden soils, while others fail miserably. What we need are more selections of the better adaptable Chamaecyparis thyoides ssp. henryae. The only named cultivars we know to exist is Chamaecyparis ‘Webb Gold’, and the afformentioned Chamaecyparis ‘Red Velvet’.

The cultivar ‘Red Velvet’ matures at 12-15′ in height. Our four year old plants have reached 6′ in height. In winter, the foliage color changes from green to a reddish purple, hence the name. Thanks to Georgia conifer guru, Tom Cox for spreading this amazing selection around to collectors and nurseries. Estimated winter hardiness is Zone 7a-9b, and probably much colder.

Baby Blue Ice

We have a fairly decent collection of conifers at JLBG, but one that has really caught our eye is Chamaecyparis pisifera ‘Baby Blue Ice’. This charming dwarf was found in 1998 by Oregon nurseryman Larry Stanley as a sport of Chamaecyparis pisifera ‘Baby Blue’. Our oldest plants are now four years old and are 3′ tall x 2′ wide. The naturally dense growth and conical shape give the impression that it’s been sheared, which is not the case.

Word on the street is that it should mature around 6′ tall, but with newly discovered plants like these, we take those size predictions with a large grain of salt. Undoubtedly, mature size in the Southeast US will be quite different than in the heat-deprived Pacific Northwest.

Chamaecyparis pisifera Baby Blue Ice
Chamaecyparis pisifera ‘Baby Blue Ice’

Eye See You

Ever since I saw my first dragon’s-eye pine over 40 years ago, I was smitten, and throughout the years have been fortunate to collect several different named cultivars with this unique trait where the new needles emerge bicolor white and green. Here is our young specimen of Pinus densiflorus ‘Burke’s Red Variegated’ looking lovely in the gardens this week. This selection of the Japanese red pine, originated as a seedling from Long Island’s Joe Burke, from the cultivar Pinus densiflorus ‘Occulis Draconis’. Hardiness is Zone 5-8.

Pinus densiflorus ‘Burke’s Red Variegated’

Phallic Cypress

People, especially male landscape architects love to use Italian Cypress in their garden designs. Few evergreen plants have the insanely narrow, upright, bean-pole shape, without benefit of pruning. We can now add a North American native counterpart to that short list, which will be welcomed since Cupressus sempervirens (Italian Cypress) doesn’t thrive in our climate.

The photo below is Juniperus virginiana ‘Silver Spear’, a Mark Weathington selection of our native red cedar. Our original plant pictured below is now 8 years old and has never been sheared. Winter hardiness should be Zone 4-9.

Juniper-like False Cypress

We’ve long collected conifers of the genus Chamaecyparis (false cypress). We grow all six recognized species, but the one which is best represented in horticulture is Chamaecyparis obtusa (hinoki cypress). Selections from this species range from giant 100′ specimens to tiny dwarfs.

Our favorite has to be the the dwarf Chamaecyparis obtusa ‘Juniperoides’…the juniper-like hinoki cypress. Introduced from the UK around 1920, this century old selection has yet to be surpassed. Below is our 23 year-old specimen this spring, which thrives in our un-irrigated rock garden, planted among agaves, having achieved the massive stature of 2.5’ tall. This is certainly not where we usually recommend planting hinoki cypress, since many cultivars don’t thrive in western sun, especially without any sign of irrigation. This plant, however, continues to amaze us without any browning typically seen with chamaecyparis grown in the combination of sun and bone dry soil.

Chamaecyparis obtusa ‘Juniperoides’

Intermingling in the Garden

We love intermingling plants, often planting more than one type in the same space, where their growth habits allow them to comfortably co-exist. Here is a three year-old planting where we used ‘Gold Queen’ Hyacinth among a patch of our North American native groundcover juniper, Juniperus horizontalis ‘Bar Harbor’. Despite what many folks seem to think, there are no laws that plants in the garden can’t touch each other, so how about some more hand-holding in the garden.

Glowing Podocarp

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.

A Little Diamond

Cryptomeria japonica ‘Little Diamond’ is one of our favorite dwarf Japanese cedar selections, this one from Holland Konjin Nursery prior to 1990. This specimen at JLBG is five years old and measures 2′ tall x 3′ wide. At maturity, we have seen these reach 4′ tall x 8′ wide.

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.

Golconda

I remember first meeting the golden foliaged Leyland cypress back in the early 1980s at the JC Raulston Arboretum, and falling in love. Despite eventually removing almost all of our other cultivars of Leyland cypress from the garden due to size issues, we still treasure this gem. For us, x Cuprocyparis leylandii ‘Golconda’, which was discovered in the UK in 1972 as a branch sport, has been a wonderfully slow grower in our climate….4′ tall in 25 years. We understand it grows much faster in climates with cool summer nights, but we’re thrilled ours is slow enough to stay garden-sized.

Mamba Combo

Every day as we take the short drive home, we’re greeted with this combination of Chamaecyparis obtusa ‘Fernspray Gold’ and a new black elephant ear. We encourage people to be more conscious of textures, forms, and colors in the garden, and to notice how plant placement can be used to create such really pleasing moments.

Trolling in the garden

Trolls and trolling are generally associated with something unpleasant, so it’s quite bizarre to have such a name associated with an amazingly delightful plant. Gingko biloba ‘Troll’ is a superb dwarf gingko with lacy textured leaves that has been quite a star here at JLBG. Our six-year-old plant is now 3′ tall x 3′ wide as of this week.

Is that really yew?

While folks from “up north” know yews (Taxus), they are far less likely to know its doppleganger, the false yew (Cephalotaxus). I’ve always considered the two fairly interchangable, so was fascinated when DNA showed they actually belong to different plant families, which aren’t really closely related…other than both being conifers. Taxus is now in its own family, Taxaceae, and Cephalotaxus now resides in its own family, Cephalotaxaceae. For most gardeners, the important thing to know is that deer will consume taxus, but not cephalotaxus.

Below are a few favorites from the JLBG gardens. Cephalotaxus harringtonia ‘Brooklyn Gardens’ is a much wider leaf plant than the better known Cephalotaxus ‘Duke Gardens’. Mature size of ‘Brooklyn Gardens’ is 2′ tall x 14′ wide, so it functions as an evergreen ground cover in either light shade or sun.

Cephalotaxus harringtonia ‘Brooklyn Gardens’

Our oldest plant of Cephalotaxus ‘Duke Gardens’ is now 27 years old, and measures 3′ tall x 12′ wide. Here it is growing in fairly deep shade.

Cephalotaxus harringtonia ‘Duke Gardens’

Cephalotaxus harringtonia ‘Golden Dragon’ is a much smaller selection with bright golden foliage. Our five year old plants are 2′ tall x 4′ wide. The gold color only shows with a bit of sun.

Cephalotaxus harringtonia ‘Golden Dragon’

Bruce and his conifers

We recently visited conifer collector Bruce Appeldoorn at his nursery in the tiny town of Bostic, west of Charlotte, NC. Not only are the gardens amazing, but Bruce has transitioned from his career in landscape design/installation, to an amazing dwarf conifer nursery. He now sits atop the throne, having what is almost certainly the top conifer nursery in the Southeast US. Most everything is propagated here from either cuttings or grafting. He is part of a small contingent of regional broom hunters, who seek out and graft dwarf witches broom mutations from area pine trees. You can find out more about how to visit or order here.