Looking lovely in the garden now is the Purple Velvet Bean vine, Mucuna cyclocarpa. This lowland native to Southeastern China makes a superb deciduous vine that flowers non-stop from mid-summer until fall. To us, the bizarre fleshy flower clusters look like those characters from the old Fruit of the Loom commercials. Interestingly, we must not have the pollinators it needs in our region, since it never sets any seed unless hand pollinated. One of the other species, Mucuna pruriens, has been widely studied, and found to have countless medicinal properties, but it doesn’t seem that M. cyclocarpa has been studied so far. All plants in the US seem to trace back to the former Yucca Do Nursery, who obtained seed from a visiting Chinese researcher.
Okay, raise your hand if you grow Orbexilum lupinellus in your garden? I’m still looking for hands out there… This endemic to longleaf pine/wiregrass habitats in the Coastal plain from NC south to Alabama, is a delightful rock garden plant, that’s made itself right at home at JLBG, flowering beautifully in late August/early September. This is growing in a rarely irrigated rocky section and has thrived in both the heat and drought. It’s probably not showy enough to offer commercially, but we sure enjoy it.
What would you say if I told you that virtually everything you know as a mimosa, isn’t? In fact, the commonly known mimosa is actually an albizzia. Albizzia julibrissin, native from Japan through to the Transcaucuses, was brought to the US back in the 1700s as an ornamental. Back in the day, it was actually thought to belong to the genus Mimosa, but this error was corrected by 1806, but as you can see, old names die hard. Although beautiful, albizzia is a prolific seeder, so is rarely planted any longer.
Interestingly, virtually no one grows any of the 25 North American native species of true Mimosa. Below is our plant of Patrick’s collection of the Southwest US native, Mimosa dysocarpa in flower now. This 3-6′ tall, highly thorny shrub, grows natively from 3,500′ – 6,500′ in the dry deserts of Texas, Arizona, and New Mexico. So far, it seems to be liking its new home in NC. It’s a particularly good food for bees, butterflies/moths, and birds, while the fruit is adored by quails.
Flowering well in the late summer at JLBG is the florally magnificent banana, Musa ornata. Native to Myanmar, Northern India, and surrounding regions, it isn’t typically winter hardy in Zone 7b. This is Hayes Jackson’s selection, Musa ornata ‘Anniston’, which sailed through last winters 11 degrees F.
Looking and smelling wonderful in the garden this week is our 2022 introduction, Hosta ‘Summer Snowstorm’. We love late-flowering hostas with large fragrant flowers, and this one doesn’t disappoint, with foliage that still looks great in late summer.
Flowering now in the garden is one of our favorite crinum lily species, the South African native, Crinum buphanoides. The name comes from its resemblance to another South African member of the Amaryllid family, the less winter hardy, Boophane.
Despite a few folks who tell us they’ve had trouble growing this, our experience is quite the opposite. We have it growing in many locations (since 2005) around the property and all are thriving. We grow ours in sandy loam that’s been heavily amended with compost. Hardiness is Zone 7b-9a, at least.
Looking lovely in the bog garden during August is the native coastal bog asphodel, Tofeldia racemosa (aka: Triantha racemosa). This little-known native of the Southern coastal plain can be found in moist lowlands, often growing with pitcher plants. Tofelida is so unusual that no other plant family would accept it, so it had to create its own, Tofieldiaceae. Recent DNA has even kicked it out of its genus, and into its sister genus, Triantha. Hardiness is Zone 7a-9b, at least.
We have a large collection of silphiums at JLBG, but unfortunately most have limited garden value since they splay apart and often completely fall over when in flower. While they’re loved by native bees, we have been frustrated to not find many that are mainstream garden worthy. One that has been impressive in our trials, however, is the southeast US native whorled rosinweed, Silphium trifoliatum var. latifolium. These 15 year-old clumps at JLBG, which originated from Scott County, Mississippi are now 6-7′ tall, and quite garden worthy. Hardiness Zone 5a-8b, at least.
On my very short commute home, we’ve designed beds along the way that help relieve the stresses of the day. One of my favorite beds in summer is this combination of Allium ‘Millenium’, Sinningia tubiflora (white), Verbena bonariensis, and Pervoskia atriplicifolia. Both the sinningia and the verbena can be a bit aggressive in some areas of the garden, but not here, where they’ve all reached a happy equilibrium. Not only are they visually attractive, but this bed is awash with pollinators, despite none of these plants being southeast US natives.
The Taiwan endemic, Lilium formosanum is just wrapping up its summer floral show in the garden. I’d be hard pressed to imagine a garden without this garden showstopper. The cluster of huge fragrant flowers top the 6-7′ tall, sturdy stalks, starting in early August. We allow a few seed to drop each year, which results in patches scattered around the garden. The fragrance is as sweet as any honeysuckle you can imagine. Soon, you’ll have enough to also fill your home with cut arrangements. Hardiness Zone 6a-10b.
After the flowers fade, the seed pods turn upward, making a classy candelabra that dries atop the stalk for a great winter ornament in the garden or they can also be used in dried arrangements.
No garden is complete without at least one rudbeckia. Looking good in the garden now is the lovely Rudbeckia umbrosa. Formerly recognized as a a subspecies of the more commonly grown Rudbeckia fulgida, this is a very different plant that’s taller, and with very hairy foliage. For us, this moist woodland native tops out between 30″ and 36″, with a much more open habit. Although it’s little known in gardens, it’s actually native from the Carolinas west to Missouri. Zone 5a to 8b.
One of the many hardy sinningias that has really impressed us during the last few years is Sinningia ‘Amethyst Tears’. Here is our garden clump, flowering its head off in the middle of August. You’ve probably never heard of this, since it’s an unintroduced Yucca Do selection from plantsman Wade Roitsch.
The variegated hardy hibiscus, H. ‘Summer Carnival’ has looked outstanding all summer. This Hans Hansen creation has both variegated leaves and flower buds. We’ve had these in the garden since 2017, and they continue to excel. Moist to wet soils and full sun are ideal, but they handle short term drought just fine. Hardiness is Zone 4a-9b.
July has been a great month to enjoy the floral show of the most winter hardy member of the genus Aloe. Our plant of Aloe cooperi, below, is happy as can be, growing in half day sun in our crevice garden.
Back in the early 2000s, we grew the spiral ginger, Costus speciosus for many years, before finally loosing it in a very cold winter, but its potential hardiness has always fascinated us. In 2013, Georgia plantsman Ozzie Johnson collected a specimen near the border of North Vietnam and Southern China at 3,900′ elevation. Below is Ozzie’s collection this week at JLBG, after our recent winter of 11 degrees F. The same plant, growing in Atlanta, survived 5 degrees F this winter without protection, so I think we can safely say we have a Zone 7b hardy form. This exceptional clone has been named Costus speciosus ‘Wizard of Oz’. It will take a few years to build up stock, but we’ll get this one ready as fast as possible.
It’s that time of year, when the surprise lilies, Lycoris, that we have scattered throughout the garden begin to pop. Actually, due to our early summer rains, they began popping in early July this year, 2-3 weeks ahead of normal.
Surprise lilies are divided into two groups, based on when their leaves emerge….fall (October) or late winter to early spring (March). Those with fall emerging foliage are generally not winter hardy north of Zone 7a, while those with late winter to early spring emerging foliage can usually tolerate temperatures of Zone 4/5.
Here are a few recent images from the garden from our world-renown collection of 1,090 different selected clones. The spring-foliaged hybrid, Lycoris x squamigera is the most popular clone, and be seen in gardens from Minnesota south.
Lycoris x incarnata ‘Blue Queen’ is another spring-foliaged hybrid that’s yet to hit the market.
Lycoris x straminea ‘Caldwell’s Original’ is a hybrid of the late Sam Caldwell, who is one of the first breeders who devoted his life to understanding the genus Lycoris. This is a fall-foliage emerging hybrid.
Over a decade ago I decided to try planting the native Frogfruit (Phyla nodiflora) in the maritime grassland exhibit at the South Carolina Botanical Garden. To my amazement, this species that I knew of from the fringes of saltmarsh in the Lowcountry thrived in both wet and dry soils of the upper Piedmont of South Carolina! The plant has proven to have incredible versatility and grows well in sand or clay and can be flooded for weeks and completely dry as well. Unlike many other plants that can accommodate such diverse conditions it isn’t so ugly that only a mother could love it, in fact, it’s charming.
Frogfruit is a low (4” tall) trailing groundcover with 1.25” long leaves that forms a solid mass of foliage but lacks deep root structures and thus does not compete with deeper rooted structural element plants. The flowers are pale pink to lavender and resemble tiny lantanas (a close relative). The flowering season here in the south begins in April and can continue through hard freezes (typically November) but may produce flowers year-round in mild winters.
Our plants, Phyla nodiflora ‘Ramble On,’ are from a Charleston County, South Carolina collection along the margins of a wet ditch (freshwater), but the species has an amazingly wide range being found from New Jersey west to California and throughout the tropical regions of the world. Another species, Phyla lanceolata, is a more upright plant, with a similar range (but extending north to Ontario) it has longer leaves and is generally less showy as a groundcover.
This is the ideal living mulch for tough areas of your landscape. It spreads rapidly but is easy to keep contained by trimming the edges of your patch. We placed it in one of our pond overflow pits and were amazed to see it completely transform a time-sink of constant weeding into a mass of lovely little flowers while allowing the Hymenocallis and Hibiscus to continue to rise through the groundcover without obstruction.
The flowers are favored by skipper butterflies, particularly the smaller species and there is an all-day-long collection of hundreds on our patch every day. In addition, small flies, native bees, sweat bees and tiny wasps are fond of their constantly produced flowers. The leaf and stem color ranges from green to deep purple depending on the environmental conditions—generally, the more exposed to sun, intermittent drought or salty soils, the more purple in the plant. If the goal of your garden is to increase the production of life by filling all your spaces with plants that are loved by insects while at the same time reducing the need for mulch and weeding, this plant is definitely worth a try. Look for this in the near future. – Patrick McMillan.
Looking lovely in the garden this week is the amazing native small tree, Aesculus parviflora var. serotina ‘Rogers’. Despite this amazing plant being native only in Alabama, it thrives in gardens well north of Chicago. This named selection was discovered in the early 1960s in the yard of University of Illinois professor Donald Rogers, and named because of its more floriferous nature, as well as its more pendulous flower spikes.
The latest member of the clumping monardas of the Electric Neon series is ‘Electric Neon Purple’. Here it is in our garden this summer, looking absolutely fabulous. Look for this in our upcoming Fall catalog.
We’ve tried a number of Caryopteris x clandonensis cultivars over the years, and most fail to survive more than one of our hot, humid summers. One recent exception that surpassed all of our expectations is the amazing Caryopteris ‘Gold Crest’. Below is a mid-July image from the garden.
From the incredibly fragrant foliage to the color, to the pollinator friendly flowers, this is one amazing plant for a well-drained sunny spot in the garden. Our clumps have matured at 3′ tall x 5′ wide, so allow enough room. Hardiness is Zone 6a-9b.
Erythrina herbacea, commonly known as coral bean is an amazing southeast native, hailing from South coastal NC to Texas. Our plant of the coral pink Woodlander’s Nursery selection is looking fabulous in the garden this week. This deciduous perennial regrows from a large underground caudex each spring, only emerging after June. It’s drought tolerance is legendary, and as you can imagine, it’s a treat for hummingbirds. Hardiness is Zone 7a-10b.
We love the way Laurentia fluvitalis forms a flowery skirt around the base of Tricyrtis lasiocarpa. This combination has thrived for years in a part sun garden location, where it receives full sun for 3-4 hours daily. The soil moisture is average to dry.
Below is our 5 year old clump of Commelina erecta looking absolutely dazzling, as it does each spring and summer. Commelina erecta is an amazing perennial, virtually unknown in horticultural circles, despite being native from 30 of the 50 states (Minnesota to New Mexico). Our collection below is from Elbert County, Georgia.
Each plant forms a 4′ wide mat of fleshy green foliage, highlighted by erect 1′ tall flowering stems. The stems are topped from July through September with rich pure blue flowers (a rarity in the hardy plant world). Although each flower is only open for a day, the succession of blooms rivals most annuals. So, why isnt’ this grown more? In the wild, it’s a fairly sparse plant, since it occurs naturally in the light/open/partial shade. Consequently, most authorities encourage you to plant it in similar conditions. Most references also write about its potential weediness, which raises all kinds of red flags.
In our trials, we have found that it grows and flowers far better in full sun. I can’t imagine why anyone would want to put this in the shade. Although it has legendary drought tolerance, it also grows great in moist soils.
Our selection from Georgia produces very few if any seedlings in the garden, so after 5 years of growing in excellent garden conditions, we see zero signs of weediness. Did I mention that it’s a great food for quails, and doves? Winter hardiness is most likely Zone 4a-9b.
So, the question is—do you think anyone would buy this if we propagated a few?
We have been playing around with the genus Polygonella since 2000, but have still only grown 3 of the 11 US species so far. We are fascinated why these native, highly drought-tolerant members of the buckwheat (Polygonaceae) family aren’t more widely grown.
The common name of jointweed, probably is the biggest factor in their lack of popularity, but then botanist aren’t usually known for their marketing prowess. The plants do have joints, but they are far from being weeds. Polygonellas look like miniature subshrubs of obscure green joints until they burst into flower with hundreds of tufts of small white flowers, that are covered by all kinds of bees.
Below is a current photo of our 4-year-old clump of Polygonella americana. In my humble opinion, honeybee keepers should be planting these everywhere, since they flower during what is known as the “nectar dearth” season, starting here in June. For us, Polygonella americana flowers from June until October. Our plant is growing the un-irrigated crevice garden in a Permatill dominant soil, since great drainage is essential.
The lovely Lysimachia ‘Persian Chocolate’ is looking scrumptious in the garden this week. This amazing 2004 Darrell Probst introduction is 20 years old this year. Here is one of our original patches, still thriving. We have found slightly moist soils and part sun produce the best specimens. It also makes a great hanging basket/container specimen. Hardiness Zone 6a-9b.
We always look forward to the start of summer, when the summer lily show begins. These summer lilies include mostly Asiatic lilies, and their hybrids. Our particular interest are in lilies that are taller than 4′ and have pendant flowers. The shorter Asiatic lilies, and those with upright-held flowers may look great in a container, but they have little design value in a naturalistic style garden. Since some of the lilies are top heavy due to the massive weight of the flowers, we recommend varieties with sturdy stems.
Be sure you can stand the fragrance, since most hybrid lilies are so fragrant, they blow gardenias out of the water. Because these lilies have little foliage, they can be planted into masses of other plants without any detrimental effects. The flower stalks seemingly appear out of nowhere in early July, and fade into obscurity when they are finished.
Below are a few favorites we photographed recently in the garden.
With what seems to be an endless array of Hydrangea paniculata cultivars entering the market, July has turned the garden into a snow white scene. The Asian Hydrangea paniculata was first published as a new species in 1829, but was not grown in the Americas until Arnold Arboretum director, Charles Sargent brought back seed from an 1892 expedition to Japan. That original plant, now, 131 years old, measures 16′ tall x 25′ wide. I’m not saying you need to plan for your Hydrangea paniculata to reach 131 years old, but the average of a house in the US is 46 years, so logic says we should at least plant for a 50 year mature size.
Below is our clump of Hydrangea ‘Rensun’, which is marketed under a completely different name, Strawberry Sundae. The introducers of this lovely clone tout this as maturing at 5′ tall x 4′ wide, but our 6 year old specimen is already 7′ tall x 11′ wide. Based on that growth rate and the mature size of the species, I’d expect it to reach 14′ wide x 22′ wide in 50 years. It’s truly fascinating why it’s so difficult to for plant breeders to get more accurate measurements before these plants are introduced to market. One can only imagine the maintenance problems caused when you locate plants based on the size given on the plant tag, only to have the plant get 2-4 times as large as your space allows.
Since we’ve installed several new bog gardens at JLBG this year, we’ve been experimenting with a number of new bog plants. One wonderful surprise has been Parnassia wightiana, an Asian relative of our native species, P. asarifolia, caroliniana, and grandifolia. The fimbriate flowers have been a real treat to watch. These aren’t the easiest plants to grow, and we were 0 for 9 with the 9 species we’ve tried, prior to building much better bogs, thanks to Patrick’s instructions. We’re now on the lookout for other species that might also thrive in these conditions.
For baseball fans, you know the Say Hey Kid as the great Willy Mays, but in horticutlure, we have a Say Hey Kid also, Arisaema sahyadricum (say-hey-dricum). This little grown, Jack-in-the-Pulpit hails from India, where it was just discovered in 1993. Compared to most jacks that flower in the spring, this is a summer flowering species. Our plant has thrived in open, dry shade since 2014.
Through the years, we’ve trialed over 130 different agapanthus species and cultivars. One we currently have on trial that has us in love is Agapanthus ‘Quink Drops’. Not only are the buds near black and the flowers dark blue, but the sturdy flower stalks have reached 5′ tall. This is unquestionably the tallest agapanthus we’ve ever grown–a welcome contrast to all the overly short new introductions. This English selection from nurseryman Graham Gough, is named after a cough drop. Later this year, we’ll be chopping up our only clump to start the propagation process.
A few years ago, we propagated and offered what we think is a really cool native perennial, closely related to baptisia, Orbexilum psoralioides. That experiment was a flame out, as sales were some of the worst we’ve ever experienced. We dumped most of the crop, but planted several in the garden, where we continue to grow them today. The photo below is our patch in flower today. They grow similar to a baptisia, but smaller in all parts, and flower about six weeks after most baptisias have finished. These genetics are from a population about 30 minutes from JLBG.
Orbexilum, formerly Psoralea psoralioides, ranges from Illinois south to the Gulf Coast and west to Texas. It’s quite easy to grow, so perhaps the name just frightened people away. It’s really disappointing for us when we track down a great new plant, get it photographed and propagated, and then no one is willing to give it a try. Perhaps the box stores just make it much too easy to all buy the same, cookie-cutter plants so that all our gardens look the same. Unfortunately, the pollinator need much more diversity than you’ll usually find at these venues. Hardiness is Zone 6a-9b, at least.
Late spring is a great season for clematis at JLBG, but one that’s particularly of interest is the recently named (2006) Clematis carrizoensis, which hails from a very small region of East Texas. It’s not been around long enough to officially be listed as Federally Endangered, but that’s most likely where it’s headed. This new species is part of what’s know as the Clematis viorna complex. In the garden, it’s a short vine, but we chose to let it have its way with a century plant, which provides a lovely structure for the months of flowering.
I’ve been fascinated with cigar flowers since I was in my teens, only to find out years later that some were actually winter hardy here is Zone 7b. In flower now is one of my favorites, Cuphea cyanea ‘Ashevilla’. This gem looks so dainty, that it’s hard to imagine it making it through a winter, but here it is again this early summer, having survived for a decade in our gardens. Thanks to Asheville, NC gardeners Peter and Jasmine Gentling for sharing and alerting us to its winter hardiness there.
Looking lovely in the dryland garden now is the amazingly vigorous Agastache ‘Queen Nectarine’. This amazing giant measures 3.5′ tall x 3.5′ wide, and is adorned at any given time, May through October, with hundreds of flowers, perfectly designed for hummingbirds. Many of the non purple-flowered agastaches struggle in our hot, humid, rainy summers, but not this one. Hardiness zone 5a to 8b.
The purple-leaf eldeberry, Sambucus ‘Chocolate Marzipan’ is looking quite stunning in the garden. This is the first purple-foliage selection to thrive in our hot, humid climate. Envious of the English garden magazine photos, we have searched for over three decades to find one that would perform for us–Eureka!
Four years ago, we embarked on an experiment to see how well Fuchsia ‘Sanihanf’ would grow in an unprotected hanging basket, left outdoors to the elements all year. The parent species, Fuchsia magellanica is fine in the ground to Zone 6, but has no tolerance of our summer heat.
Fuchsia ‘Sanihanf’ was developed from Fuchsia magellanica and other heat tolerant species, and released in 1997, by the Suntory breeding company of Japan. It has both great heat tolerance, as well as tolerance to our winters when grown in the ground.
Typically, a plant grown in a container above ground loses around 20 degrees F. in hardiness, when the roots aren’t protected, so we weren’t sure how cold our basket plants would survive. The photo below is our basket last week, having now been through low temperatures of: 23F (2019/20), 20F (2020/21), 16F (2021/22), and 11F(2022/23). Although they look like dead sticks until mid-May, they have once again burst forth with great vigor. They are watered through the summer, but receive no supplemental water other than rainfall from fall until spring. We continue to learn amazing things, since we don’t fear killing a few plants along the way in the name of science.
Clematis ‘Sapphire Indigo’ is looking quite stunning in the garden. This fascinating clematis isn’t a vine or a clump. It could be best referred to as a short sprawler. We’ve used it throughout the gardens as a groundcover filler between both shrubs and other perennials. It doesn’t actually spread, because in the winter, it dies back to a tight rootstock. We find this absolutely exceptional, flowering for us from spring through early fall. Hardiness is Zone 4a-8b.
In the crinum lily world, a yellow flower is considered the holy grail by plant breeders, since it only naturally exists in the Australian crinum species, Crinum luteolum. Two other species which occasionally show a yellow blush in the flower are Crinum bulbispermum and Crinum jagus. Crinum luteolum is completely ungrowable in the Southeast US. Consequently, we must find yellow pigment from the other two species.
Many years ago, a secretive California crinum breeder distributed a fuzzy Sasquatch-like photo of what was supposedly his yellow flowered crinum, derived from a white-flowered Crinum bulbispermum. The plant itself has never been seen in person, despite assurances from the breeder that it still exists. In 2008, the breeder agreed to sell us seed from his parent plant, with the caveat that it wouldn’t look like the parent.
Below is the best clone that we selected from our first set of seedlings from Crinum ‘Yellow Triumph’. As you can see, the flower is virtually all white, except for a chartreuse green base. Since it was a nice flowering clone, we gave it the name Crinum ‘White Swans’.
Since 2008, we have repeatedly self-pollinated our original seedling selection, each time selecting those offspring that showed the most yellow color. Over time, the best seedlings were crossed with each other, and the selection process continued.
Fast forward to 2023…15 years after our original seedling flowered, we finally have plants that are showing a decent amount of yellow in the flowers. The yellow shows best as the flowers open in late afternoon. Below are two of our best 2019/2020 seedlings. While these aren’t yet a finished product, we are seeing the proverbial gold light at the end of the long tunnel.
Looking stunning now is one of our favorite native shrubs, the golden leaf selection of Hydrangea quercifolia, named ‘Little Honey’. Our plant below is now 19 years old, and measures 4′ tall x 7′ wide. There are few woodland plants that can brighten a corner the way this gem can–and this is without the spikes of white flowers. Hardiness is Zone 5a-9a.
One of the nice surprises after our 11 degree F freeze was how well our Escallonia ‘Iveyi’ fared. Few people on the US East Coast are familiar with these South American woody members of the Escalloniaceae family.
Escallonia ‘Iveyi’ is actually a hybrid that originated at the UK’s Caerhays Castle, where it was discovered as a seedling between Escallonia rosea and Escallonia rubra. Our plant should mature at 10′ x 10′. In mid summer, this amazing selection is smothered in fragrant white flowers.
All the literature we’d been able to find, indicates it is only hardy to 14 degrees, but that’s another reason we don’t let our plants read gardening books or browse the Internet. Our plant was grown from cuttings from an old specimen at the SC Botanical Garden in Clemson.
Great new plants for the garden do sometimes just happen. They can occur as a spontaneous sport from an existing planting, as a seed selection that has much better garden traits, but many of our most useful and ecologically important plants in the garden have their start in exploration. I was thinking about this today as I observed the tightly-clumping overwintering rosettes of one of our newest introductions to the JLBG—Oenothera riparia, Riverbank Sundrop.
Sundrops hold a special place in my heart. My grandmother loved them and had large swathes of the old pass along yellow standard Oenothera fruticosa/tetragona in her extensive garden. Every June they would burst into flower for a brief week or so, bringing a brilliant light and foil to her many glorious iris. As I mature, I have come to value plants with connections to our being but also the value of similar plants that can provide the same nostalgia while giving us much more in the landscape.
A plant known as Riverbank sundrops may be a perfect example of a great garden plant that is native to the Southeast and provides more of what gardeners love, while also providing the native insects and other wildlife an abundant resource.
Oenothera riparia was described by Thomas Nuttall in 1818 from plants collected along the Cape Fear River near Wilmington, NC. Nuttall provided a very full description of the plant (for the time) though he presumed it to be a biennial—it is in fact a long-lived perennial. J.K. Small recognized the species in a segregate genus as Knieffia riparia in his 1903 Flora of the Southeastern US. In 1937, Munz reduced the species to varietal status as Oenothera tetragona ssp. glauca var. riparia, and after this it was essentially lost to the minds of taxonomists and plant enthusiasts being considered merely part of the immense variability of Oenothera fruticosa by Radford, Ahles and Bell (1968).
In the mid 1990’s while working in the tidal freshwater swamps and marshes of South Carolina, Richard Porcher and I encountered this species growing at the bases of Bald Cypress trees, on stumps, and on floating logs just above the high-water tidal line on the Waccamaw, Pee Dee, and Edisto Rivers. My frustration with its identification led me to the name Oenothera riparia and its recognition as a completely and consistently distinct taxon—which is very unusual in a genus known for its morphological variability and messy taxonomy.
This plant is smooth (lacking hairs) throughout with thick textured dark-green leaves and a very bushy habit—it does not produce long stolons or rhizomes, so it forms a dense clump. The stems generally range from a foot to nearly 3 feet in height and the thick stems become semi-woody, providing a stiffly upright growth form. Rather than a single burst of flowers this species produces masses of flowers over the entire summer (June-late August) with sporadic flowering later in the season.
Imagine, here we could have a sundrop that won’t spread like wildfire, doesn’t flop, and flowers for month after month! Sounds like everything you would want in a plant. There is only one problem, it hasn’t been cultivated. This is where the adventure continues and as we embark on this adventure, I would like to take you along for the ride. There is so much that goes into identifying a potentially great garden plant, evaluating it, and bringing it to the trade.
Our initial collections were made this August (2022) when Zac Hill, my wife Waynna, and I were traveling through the SC coastal plain. We made the stop at the Edisto River in Colleton County where I had seen the plant many years before and just like I remembered, there they were, full of seed and with some flowers still present. The only problem is that they were growing far out in the water along the bases of trees! The Edisto is a blackwater river with a large tidal amplitude at this location and it was full on high tide. If you’re a field botanist you forget entirely about the things that concern other more rational folks, like the multitude of large Alligators, and make for the plants. I found some low branches on a neighboring willow tree that kept my feet in only a couple feet of water, and balancing on the branch, in the water, made my way all the way to the edge of the river where a fabulous floating log provided an abundance of seeds and two small plants from a large cluster of individuals. The only casualty was my prescription glasses which promptly fell from my head into the depths of a rapidly moving Edisto River (my wife will not easily let me forget the cost of this single collection). The first step in the process of bringing a new plant into production is done.
Our two small divisions were placed directly into the sun garden at JLBG and the seed was sown. For this plant to be successful in a garden it must be able to not just survive but thrive in a common garden condition far away from its very narrow niche at the very upper edge of the water along the Edisto. You might think this would be unlikely, but other incredible garden plants are entirely found in wetland communities and thrive under very different conditions in the garden. A good example of this is found in another of our introductions, Eryngium ravenelii ‘Charleston Blues’, which comes from high pH wetlands not too far away from the Edisto River.
Will it be hardy here? Will it survive under normal garden conditions? Will it maintain its distinctive and garden-worthy features? Well at least part of this can be answered already. Our tiny divisions are now large overwintering basal rosettes. The plants have not thought about running away from their tight cluster, and they grew very well during their first autumn in soil that was not kept overly moist.
The real test lies ahead. What will the plants nature be under cultivation? Will it be as good as I think it could be? Will it be better? One can only hope, put in the labor, and follow along to find out the end of this story for Oenothera riparia. It could provide all of us with a stately and handsome bit of nostalgia with far greater design and utilitarian use for humans and our native biota. What’s more, there are other seemingly great garden-worthy Oenothera out there—not in far-flung locations but right here in the Carolinas. Have you ever heard of Oenothera tetragona var. fraseri? If not, look for us to tell you more about that in the years to come, there’s a fantastic form with huge flowers in the Blue Ridge escarpment of South Carolina!
Patrick D. McMIllan, PhD
One of my most lustful plants has been the super cute Euphorbia clavarioides var. truncata. I first ran into this fascinating poinsettia cousin at the Denver Botanic Gardens in the 1990s, and have subsequently killed it 5 times, prior to the construction of our crevice garden. Now, our specimen below is 2.5 years old and thriving. The key is perfect drainage and no water in the winter.
Below is a giant clump, which we saw in the wilds of South Africa in 2005. These massive clumps are considered to be well over a century in age, so our little patch has a lot of growing to do.
You go straight through to the round of botanical superstars if you recognize this little-known southeast native (SC to Florida), Piriqueta caroliniana. This Patrick McMillan collection from coastal SC has thrived all summer in our full sun rock garden, flowering constantly, with new flowers opening every other day. This oddity is a member of the Turneraceae family, which comprises nine other equally obscure genera. We’ve yet to determine if this will actually make a good garden plant, but evaluation continues. Hardiness north of Zone 8a is unknown.
One of the stars of our late summer/early fall garden has been our selection of Chrysopsis mariana ‘Little Miss Sunshine’. We made this roadside collection of this East Coast native in 2020 in neighboring Orange County, NC, unsure of what we had collected, but loving the purple stems of this clone. This planting in our rock garden has produced an amazing 18″ tall x 2′ wide specimen that glows for months. Dry soils and at least half day sun are the keys to success. We’ll start propagating this showy, clumping native perennial in spring. Winter hardiness is Zone 4-8.
We’ve had Salvia ‘Rockin’ Deep Purple’ on trial since 2018, and it’s now headed for our January Plant Delights catalog. Although we love the Argentinian Salvia guaranitica, it spreads far too fast to be useful in many of our garden beds. We have been trialing a number of hybrids with Salvia guaranitica and an array of different clumping species to find one that has winter hardiness, but doesn’t take over the garden.
Salvia ‘Rockin’ Deep Purple’ from California’s Brent Barnes, has lived up to all of our expectations, as long as you have enough space. For us, a single clump measures 5′ tall x 10′ wide…a far cry from the 3.5′ tall x 2.5′ wide size that’s often marketed on-line. Below is an image of the flower power it’s still showing in early October. The bumblebees love it as much as we do.
How many folks are growing Hypericum hypericoides (St. Andrew’s cross)? The name translates to hypericum that looks like a hypericum….duuuh. We love this native shrub which hails from New Jersey southwest to Texas. St. Andrew’s cross typically matures at 2.5′ tall x 5′ wide and adorned from May through September with small, light yellow flowers, which form an “x”, hence the common name.
In the wild, Hypericum hypericoides is usually found in slightly acidic to slightly alkaline sandy soils, often in pine savannas, but in cultivation, they seem quite adaptable to an array of garden conditions from sun to part sun. In form, it resembles a Helleri holly with yellow flowers. The photo below is a 2 1/2. year old plant at JLBG. Winter hardiness should be Zone 6a-8b at least.
Flowering this week at JLBG is the amazing Miscanthus transmorrisonensis. Many gardeners, who blindly believe everything they read/hear think the genus miscanthus is the horticultural version of the devil itself. Like everything in life, it’s all about those pesky details, which so many people simply don’t want to be bothered with.
Most miscanthus in the horticultural trade are selections of the species Miscanthus sinensis. Some selections of that species reseed badly and should be avoided in gardens. Others are sterile or nearly so, and unquestionably still deserve a place in American landscapes.
If we make good/bad evaluations at the species level, what would happen if visitors to the earth had their first encounter with a Homo sapiens that was a less than ideal representative of the species at large. They could easily assume that the entire species was a problem and should be eliminated. It’s fascinating that such species based prejudices are acceptable with ornamental plants, but not with people.
Then there are species, which have proven themselves to be complete without seed in our climate, such as Miscanthus transmorrisonensis. All plants in cultivation all appear to be derived from a 1979 Ferris Miller (Chollipo Arboretum)/ Paul Meyer (Morris Arboretum) collection at 9,500′ elevation on Taiwan’s Mt. Daxue. We have grown this for 30 years in rather good conditions, and have yet to see a single seedling. The beauty of this species is that it flowers continuously from summer into fall. I guess it’s too much to ask for environmental fundamentalists to actually pay attention to facts.
We think Juliet would agree that Cuthbertia rosea is one sweet perennial. Looking great now is the southeast native (Maryland south to Florida) spiderwort, Cuthbertia rosea, which for us, begins its flowering season in spring, and continues sporadically through the summer months. Native primarily to dry sand, this easy-to-grow perennial has exceptional drought tolerance. Like all spiderworts, the flowers open in the morning and close each evening.
This poor plant has long suffered from an identity crises due to dueling taxonomists. This poor plant is also known as Callisia rosea, Tradescantia rosea, Phyodina rosea, and finally Tripograndra rosea. Despite the naming conundrum, it’s surprising that more people don’t grow this amazing plant.
One of the little-known of the native orchids is flowering now at JLBG. Habenaria repens, aka: water spider orchid, is the most widespread (NC to Texas) of the five native habenaria species. This charmer has been at home in one of our bogs for several years and has proven quite easy to grow. Hardiness is probably Zone 7b-10a, at least.
Re-appropriating a line from the late Buck Owens, it’s crinum time again. Crinum lilies begin their flowering season in our climate around April 1 (frost permitting). Some bloom for a short number of weeks, while other rebloom for months. Depending on the genetics, some crinum hybrids start flowering in spring, some in summer, and others in fall, and a few flower during the entire growing season.
Crinum ‘High on Peppermint’ is one of our newer named hybrids, which starts flowering for us around June 1, and hasn’t stopped yet.
Crinum ‘Superliscious’ is another of our new hybrids that starts flowering July 1, and has yet to stop. Now that our evaluation process is complete, we’ll start the propagation process.
Crinum ‘Southern Star’ is an incredible hybrid from the late Roger Berry, entrusted to us to propagate and make available. That’s a tall order since it’s one of the slowest offsetting crinum lilies we’ve ever grown. Crinum ‘Southern Star’ is a hybrid with the virtually ungrowable, yellow-flowered Crinum luteolum, which hails from Southern Australia. For us, Crinum ‘Southern Star’ doesn’t start it’s floral display until August 1.
Gardeners in Zone 7b wouldn’t typically think of Angola (tropical West Central Africa) as a place to search for hardy perennials, but we’ve been thrilled with the performance of two natives of the region, Crinum fimbriatulum and Crinum jagus. The reason we kill so many plants is we try things that people with better sense would assume wouldn’t have a chance of the proverbial snowball.
Crinum fimbriatulum is flowering now for us, while Crinum jagus bloomed a few weeks earlier. Crinum fimbriatulum is the taller of the two, with spikes reaching nearly 4′ tall. Our plants were planted in 2009. They thrive in average to above average soil moisture.
Crinum jagus has been in the ground at JLBG since 2015. It’s a much shorter plant with 2′ tall flower spikes, but with incredibly lush, attractive foliage.
We’ve been playing around with yucca breeding for almost a decade, and now have hybrids that include from 3-5 different species. Here’s a shot of one of our evaluation beds when it was in full flower recently. Flower spike height ranged from 3′ to 10′. There should be some wild and crazy introductions once our trials are finished.
I’ve been surprised to see the black swallowtails regularly enjoying the nectar of the summer-flowering daphnes…in this case, Daphne x napolitana ‘Bramdream’. Our plants are thriving, growing in our full sun rock garden.
I’m more and more impressed with Hosta ‘Miss America’ each year. Not only is this white-centered hosta amazingly vigorous, but it has one of the finest floral shows we’ve ever seen on a hosta. The steel rod-like upright flower stalks on our plant have reached 4′ tall, but as the plant grows larger, they will eventually top 6′ in height. Not wind, rain, or post office vehicle can knock down these super sturdy stalks, and the great show they provide for weeks. Our plant is 100′ from our back porch, and it shows up like a floral beacon even from that distance.
Our clump of the native, Sabatia kennedyana just finished another amazing floral show. This fabulous, but easy-to-grow perennial has a truly odd native distribution on the coastal border of North and South Carolina, on the coastal border of Massachusetts and Rhode Island, and in Nova Scotia! I don’t think I’ve ever seen such an odd, disjunct range. Sabatia kennedyana is best suited for a sunny, slightly acidic bog, but regular garden soil will work fine, if it’s kept moist. I have no idea why this isn’t grown in every garden that has the correct conditions. Winter Hardiness is Zone 6-8, at least.
I’m always amazed that so many people don’t realize that turmeric (Curcuma longa) is an amazing garden perennial. We’ve had our plants in the garden for nearly 30 years. This week, the flowers of this delightful ginger lily from Southern India emerge, looking like fancy pink pine cones. Curcuma longa is very easy to grow, as long as the soil is reasonably well-drained. Just mark the planting spot, since it usually doesn’t break ground before June. Hardiness is Zone 7b-10.
He’re a shot from our garden that we see every morning, featuring a drift of the giant, sun-loving Hosta ‘Sum and Substance‘…and much more.
Below is another shot from the same location in the garden, but looking north. Who said summer gardens need to be boring?
Most highly prized rock garden plants originated somewhere other than the Southeast US. One notable exception is Bigelowia nuttallii, or if you prefer common names, Nuttall’s rayless goldenrod. This fascinating plant resembles a whisk broom that just swept up a spilled bottle of mustard.
Named after English botanist/zoologist Thomas Nuttall (1786-1859), who lived in the US from 1808 until 1841, this fascinating plant, grown by rock gardeners worldwide, is native in only a few locations from Georgia west to Texas.
Bigelowii nuttallii makes a tight evergreen clump of needle-thin leaves, topped from mid-summer until fall with 1′ tall sprays of frothy yellow flowers…yes, those are actually flowers, but without the typical showy “rays”. Full sun for at least half a day, and good drainage are the key to success with this very easy native perennial. Hardiness is Zone 5a-9b.
Lagerostroemia ‘Gamad VII’ is looking exceptional in the garden this month. This dwarf selection, sold under the invalid trade name of Sweetheart Dazzle, is a gem of a plant, and one that has actually stayed dwarf. Our twelve year old plant is 4′ tall x 10′ wide.
Plant breeders are an odd sort…people who are never satisfied with their results, and as such are always looking to improve even the most fabulous creation. We’ve been dabbling with crinum lilies for several years, and the first photo below is one of our newest creations, Crinum ‘Razzleberry’, which is rather amazing. Despite this success, we return to the breeding fields to see what else awaits from additional gene mixing.
Crinum flowers typically open in early evening…5-7pm for us. The first step in breeding is to remove the petals, to have good access to the male pollen (the powdery tips atop the six pink thingys), and the female pistil, the single longer thingy with a dark pink knob at the top and a bigger knob at the bottom. Most crinum pollen is yellow, but depending on the parentage, some hybrids have white pollen.
The male thingy is known as a stamen, comprised two parts, the filament (the pink thing), and the anther (the part with the pollen). The female parts are known as the pistil, comprised of the ovary (bottom), the style (the pink thingy), and the stigma (the sticky knob at the tip.
In breeding, the anther is removed and the pollen is dusted on the stigma of a different plant to make the cross. Crinums produce an insane amount of nectar, so crinum breeders are constantly dodging sphinx moth pollinators, as well as dealing with the ant superhighway below as they haul off the nectar.
If your cross is successful, you will have seed forming in about a month. The seed are quite large, and must be planted immediately, since they have zero shelf life.
Once the seeds germinate it normally takes 4-5 years for your new seedlings to bloom. During the first several years you can evaluate vigor and growth habit, but the final evaluation can’t be made until it blooms.
Tired of trying to grow the conventional baby’s breath, that’s a prize perennial in the colder zones? We were, and had been looking for a substitute for years, when in 2000, one of our former staffers introduced us to the widespread native, Euphorbia corollata. Although it doesn’t look like much in deep shade where it’s often found in the wild, it explodes when given a bit of sun. Here are a couple of photos as it’s flowering season starts in mid-July.
Euphorbia corollata looks seriously gangly in a pot, so we’re confident you’ll never see this on the shelves of the box stores. Average moisture to very dry suites it fine. Although not a clumper, it’s spread it’s far from a thug, and is easy to remove it it happens to move too far. For a plant that’s native to every state East of the Mississippi (except Florida), and almost every single county, it’s shocking that every gardener isn’t growing this gem. Hardiness is Zone 3a-9b.
Even the garden insects aren’t enjoying our extended heat wave. We caught this grasshopper hiding inside the flower of the threatened Texas endemic, Hibiscus dasycalyx last week, in search of some shade. So far, we’re experiencing the 3rd hottest summer on record in the Raleigh area.
Here’s a recent garden combo that we’ve been enjoying with purple eucomis (pineapple lily), Agapanthus ‘Navy Blue, backed with Foeniculum vulgare ‘Purpureum’ (bronze fennel).
It fascinates us that such a widespread native like Eustoma exaltatum isn’t more widely grown in gardens. Often known by the common names prairie gentian or lisianthus, eustoma is prized by flower arrangers, but not gardeners. Eustoma is native from coast to coast…Florida to California, and north to the Canadian border in Montana.
In the wild, Eustoma exaltatum is a short-lived perennial that can also behave as a biennial or even an annual in some sites. The key is to plant it where it can happily reseed as we have done in our gravelly crevice garden, which is odd, since in the wild, they are found in moist meadows and streamsides.
Below are our plants in peak flower now, during the brutal heat of summer. So far, we’ve struggled to keep this happy in a container, in the hopes we could make this available, but we continue to try.
Commercially, eustoma has been hybridized ad nauseam to create better cut flowers, but these hybrids seem to have lost all of their perennial nature compared to the wild genetics. Our plant pictured below is the large (2′-3′ tall) subspecies russellianum from wild collected seed from Bastrop County, Texas.
It’s always exciting for us when the summer flowering surprise lilies begin to bloom, which usually happens here around mid-July. Lycoris are members of the Amaryllidaceae family, and are cousins of better-know bulbs like hippeastrum (amaryllis), zephyranthes (rain lilies), and narcissus (buttercups).
Since we grow over 700 different lycoris varieties, the flowering season goes all the way from now into October. Below are are few of the early varieties from the start of the flowering season.
We recently ran across this clump of the summer-flowering native (Canada south to Florida) orchid, Goodyera pubescens growing in a site near JLBG. Like a century plant, the flowering rosette dies after flowering, but new side shoots are produced for future generations. Work is being done to produce this in tissue culture so it can be made more widely available from nursery propagated stock. Sadly, most plants sold today are wild collected.
Of the 100 species of Goodyera orchid, only 4 are US natives.
This spring, Plant Delights introduced Zac Hill’s 2013 discovery of a new ruellia which he found in central Alabama. What we theorized might be a natural hybrid turned out to be a brand new species, as we were informed by botanists working on getting the plant published. We hope all native plant enthusiasts purchased this to both enjoy in their garden and for ex-situ (off site) conservation value. These are in full flower during the summer. Hardiness is unknown at this point, but we know it’s fine from Zone 7b – 8b, and most likely much further north.
Our tallest clump of Nelson’s bear grass has been in full flower for the last month, making a spectacular site. Our specimen, which has reached 10′ in height is now 23 years old from seed. This woody lily which hails from the state of Tamaulipas in Northern Mexico forms a yucca-like stalk in the garden. All of the other hardy bear grasses have green foliage, so the blue foliage of Nolina nelsonii is quite distinct. The common name of bear grass was coined on the Lewis and Clarke expedition, when nolinas were mistaken for yuccas, which at the time were known as bear grass. Hardiness is Zone 7b-10b.
One of the most amazing summer perennials we grow is the native Berlandiera pumila ‘Chocoholic’. It is unfathomable to us, why this isn’t grown in every full sun garden where it’s winter hardy. The flowers, which smell like milk chocolate, top the 3′ tall clump nonstop from May until October. In the wild, Berlandiera pumila can be found from NC south to Texas, so its drought tolerance is excellent. We rate this as Zone 7a to 9b, but that’s only because we don’t have feedback from folks in colder zones yet. Please let us know is you have this survive temperatures lower than 0 degrees F without snow cover!