We’ve been very pleased with a series of new windmill palm hybrids in the garden as we approach another winter stress test. Trachycarpus x forceps is our assigned name for crosses between Trachycarpus fortunei and Trachycarpus princeps. While most Trachycarpus fortunei is winter hardy here in Zone 7b, the lovely Chinese/Tibetan border endemic, Trachycarpus princeps, with its silver backed leaves, has not been so happy–we’ve killed four, so far.
Several years ago, we were thrilled to acquire seed of several different crosses of the same hybrid. Since all crosses between the same species must use the same nothospecific name, we assigned each with an additional seed strain cultivar names to distinguish the different parents and which was the mother and father. In plant breeding, the mother is always listed first..
*T. princeps x T. fortunei ‘Wagnerianus’ = Trachycarpus x forceps ‘Prince’
*T. fortunei ‘Wagnerianus’ x T. princeps = Trachycarpus x forceps ‘Wags’
*T. princeps x T. fortunei = Trachycarpus x forceps ‘Silver Mine’
*T. fortunei x T. princeps = Trachycarpus x forceps ‘Fortune’
Below is a 4.5 year old plant of Trachycarpus x forceps ‘Wags’–our oldest specimen.
Trachycarpus x forceps ‘Fortune’ has been in the ground for 2.5 years. This is the cross using straight T. fortunei as the mom and T. princeps as the dad.
Trachycarpus x forceps ‘Prince’, below, has been in the ground for 2.5 years also. Here, Trachycarpus princeps was the mom parent.
We’ve planted quite a few forms of our native Sabal palmetto through the years. Only two have survived long term; the the form from Bald Head Island, NC, and one propagated from an ancient specimen in Mt. Holly, NC, just west of Charlotte. Taken recently, our Mt. Holly specimen is now 22 years old. It’s been almost that long since we’ve had any to share, so we’re hopeful our plants are getting old enough to flower soon.
We were delighted to have the amazing UK botanists, John and Soejatmi Dransfield drop by this week for a visit. Both are retired scientists from Kew Garden, where Dr. Soejatmi Dransfield specialized in paleotropical bamboos, and Dr. John Dransfield specialized in palms. It turns out that John also works with podophyllum in his retirement, so we had a blast chatting about our mutual work with the genus as we wandered the garden. Both are incredibly keen plant lovers, so we hope for another visit when we’ll have even more time to wander and talk plants!
In late February, myself and local plantsman Mike Chelednik, headed south for the mid-winter meeting of the Southeast Palm Society, being held at the American Camellia Society Headquarters at Massee Lane in Ft. Valley, Georgia. I had wanted to visit the camellia garden ever since I knew one existed, but the timing had never worked out. Mike, who goes by the social media moniker, “Mike See”, is one of the foremost camellia experts, as well as a hardy palm enthusiast.
Our first stop on the way to Ft. Valley was the Atlanta Botanical Garden’s Gainesville, Georgia satellite garden, to check out the plant damage from their winter low temperatures of 5 degrees F. Although a number of plants in their trial fields were quite crispy, including most of the commercial cultivars of distyllum and even giant plants of Osmanthus heterophyllus, there were an amazing number of new plants from their recent Asian plant exploration trips that sailed through the cold.
I was particularly excited to see that a collection of the giant Begonia sillitensis from India sailed though the cold and looked ready to start growing. It was also great to see how well their large specimen of the Taiwanese aralia relative, Sinopanax formosanus, sailed through the winter. I had seen this in the wild several years earlier and felt it had a good shot at surviving in central NC.
I was especially glad to see that their amazing, conical clone of the hardy cinnamon tree, Cinnamon japonicum sailed through the low temperatures without any damage.
Their greenhouse was full of new treasures yet to go in the ground, including this Vietnamese collection of Sauromatum venosum. Virtually all of the material in the trade currently is from India, so these new genetics are quite exciting. Of course, there is always the possibility that this constitutes a newly discovered species. The velvety leaf surface makes me fairly confident this may be new. We are very fortunate to be a trial site for many of their amazing collections.
From ABG, we headed south through the highway insanity that constitutes the drive through Atlanta and south toward Macon, GA. There simply aren’t enough lanes to handle the mass of vehicles that travel this route–something you would think highway department officials would have noticed by now.
I was quite unprepared for the facilities at Massee Lane Gardens, since plant society headquarters are pretty much an extinct dinosaur of bygone eras. In this case, the Ft. Valley headquarters located in this former peach shipping hub of South Georgia, was a well-funded throwback to earlier generations. Started in the 1930s by pecan farmer, David Strother, the 160 acre property still contains pecan orchards. In 1966, Strother donated the property to the American Camellia Society.
The rectilinear facility has a “dripping with money” elegance, at odds with most of the surrounding tired town. Entering through the gift shop, a right turn takes you into the Annabelle Lundy Fetterman Educational Museum, a meeting room/display museum, which houses an absurdly extensive collection of Boehm porcelain. This room is named after the NC camellia aficionado of the same name. The late Annabelle Fetterman was the renown businesswoman CEO/owner of Clinton NC’s Lundy Packing Company.
Taking a left from the gift shop, routes you toward the lovely auditorium, where we would hold our Palm Society meeting.
About 35-40 palm nuts showed up for the SPS meeting, with several like us, driving in from 5-10 hours away. I’ve been a member of this amazing, but loose knit organization, for over 3 decades, although I think this is the first meeting I’ve attended that wasn’t held at our own Raleigh garden. We were treated to a fascinating talk by Rick Davis, on growing Cocoid palms in upstate SC. These include the jelly palms of the genus, Butia, and their hybrids. I think we all left the meeting, knowing there are far more palms we need to try in Zone 7.
Following the meeting, there was a rare palm auction thanks to member donations, followed by a tour of the Massee Lane gardens by Garden Manager, William Khoury. William and his staff of one assistant, manage and curate the entire camellia garden, which covers over 6 of the 160+ acre property. We’re sending good thoughts that they get more help to manage this extensive collection.
The garden is almost exclusively camellias, planted in large beds, with easily navigable paths winding visitors through the plantings.
While 99% of the visitors head to the garden section containing the show camellias and their hybrids, I headed to the virtually empty section devoted to wild camellia species, almost all of which were a gift from the late Dr. Clifford Parks of Chapel Hill, NC, just prior to his death. It was an interesting study, since they dropped to 12 degrees F. this winter…only a single degree higher than Raleigh, NC.
Camellia species other than Camellia japonica, Camellia sassanqua, Camellia reticulata, and Camellia sinensis, are virtually unknown by US gardeners. While not nearly as showy as the fancy hybrids, many of these plants have amazing foliage and forms, with most worthy of garden inclusion.
For the first several hours, I had the species collections to myself, until after an on-site food truck lunch, I heard a female voice recording a soliloquy about species camellias as the figure slowly sauntered from plant to plant. As I peered through the thicket, the voice was coming from none other than our NC neighbor and former PDNer, Brie Arthur of Brie Grows, who was in the area, recording a camellia segment for her Youtube channel.
By late afternoon, I had finished studying the species, and made my way over to the show camellia garden. Much of Massee Lane is devoted to camellias that are grown for flower show bloom competitions/displays. Below are a few photos from the acres of mostly well-labeled plants. There are certainly few better gardens in the southeast US to see this many camellias (over 1,000 plants) and make notes of which you’d like for your own garden. There was even a sales area devoted to some rather new and hard to find hybrids.
Heading back north toward home, we made one stop at the garden of Atlanta area plant collector, Ozzie Johnson, who maintains a large collection of mostly Asian plants at his extensive garden. As we saw at Atlanta Botanical Garden, there was extensive damage due to the single digit F low temperatures in December.
A huge specimen of Aucuba omeiensis was quite fried and we were unable to determine yet if it might possibly resprout.
The original plant of Ozzie’s introduction, Mahonia ‘Soft Caress’, also was completely defoliated, although it appeared like it would resprout.
Another of Ozzie’s introductions, the weeping Japanese maple, Acer palmatum ‘Ryusen’ was untouched. The photo is of the original plant from which all others have been propagated.
Despite most of the commercial selections of Distylum being fried, it was great to see this variegated selection of Distyllum myriocoides untouched after 5 degrees F.
Every year when we have a significantly cold winter, we are reminded of the wonder of the Southeastern native needle palm, Rhapidophyllum hystrix. This native of Northern Florida and nearby areas in the adjacent states of South Carolina, Georgia, and Alabama, is the most winter hardy palm in existence.
Established needle palm clumps have been documented to have survived -15 F to -20F. I still remember checking on the old specimen at the JC Raulston Arboretum in Raleigh after we dropped below 0F for two consecutive nights in January 1985 (-3 on Jan 20, and -9 on Jan 21). I was amazed I was to find the plant undamaged by the cold. Below is one of our many specimens in the garden after our 11 F freeze a few weeks ago.
Needle palm is generally considered to be a non-trunking palm, although with great age, it will develop a short trunk, that will eventually become decumbent. I’m fascinated why this and other native palms are never promoted by the native plant enthusiasts.
I had to chuckle as folks on several Facebook plant groups were wringing their hands in worry prior to the recent cold snap, while we were secretly hoping for even colder temperatures than forecast.
JLBG registered three consecutive nights in the teens recently; 11F, 19F, and 19F. While this was certainly not abnormal for our area, folks with very short memories thought the horticultural world was coming to an end. In reality, we recorded similar temperatures in the winter of 2017/2018, albeit a week later that year.
When we first started the gardens at JLBG, we were squarely on the Zone 7b side of the Zone 7a line. We are now on the Zone 7b side of the Zone 8a line. In order words, we have shifted about 1/4 of a hardiness zone. Since 2018, JLBG has registered three consecutive Zone 9a winters, so it’s not surprising the new gardeners or those with short memories start assuming that all kind of plants are reliably winter hardy, which is not the case.
We long for cold temperatures because we want and need good winter hardiness data, and while mild winters may be enjoyable to us Homo sapiens, we don’t learn anything about plant hardiness from those winters. So, here are a few things we learned this year.
Agave weberi ‘Stone Cold Austin’ is Patrick McMillan’s collection of Agave weberi from Austin, Texas. We’ve tried Agave weberi a couple of times prior, and could never get it through one of our milder winters. Patrick’s original plant at Clemson got large enough to flower there, so we’re hoping for the same. The older foliage is showing damage from 11F, and will most likely be lost, but the bud seems fine so far.
We’ve never had any luck with any of the dwarf Agave lechuguilla mutants we’ve tried in the garden, but this new one, shared by plantsman Hans Hansen, that we call Agave ‘Tater Tot’, had no problem with 11F. These are often sold as Agave x pumila, which actually doesn’t exist. Everyone assumed that A. x pumila was a hybrid, but when one in Europe recently mutated back to the original form, it turned out to be nothing more that a super dwarf form of Agave lechugullla.
Mangave ‘Racing Stripes’ is a plant we had high hopes for in terms of winter hardiness, but we had not had a cold enough winter to get good data. Our only reservation was that it contains genes from the tropical Agave gypsophila. Thankfully, our plant came through the 11F freeze in reasonably good shape. The wrinkled nature of the older leaves are indications of cold damage that will show up in a few more days, but the core seems intact and should re-grow.
We fully expected Bambusa multiplex ‘Green Giant’ to be defoliated after 11F and the stalks killed to the ground, but our fully exposed clump still looks like it’s mid-summer…at least from the north side.
On the south side, the same clump has fried foliage. There are typically two causes for such damage. One is wind desication when the winds are blowing from a single direction and the ground is frozen, making it impossible for the plant to replenish water lost through the foliage. During the time that our ground was frozen, our winds were coming from the West, so that wouldn’t account for damage only on the south side of the plant.
In this case, the more likely scenario is that this is due to sun scorch when the soils was frozen, since the damage is on the south side. If the canes are indeed undamaged, as it appears, new leaves should reflush in spring.
We didn’t hold out much hope for the Mexican palm, Brahea decumbens, but it sailed through 11F unscathed.
Since we know that genetics matters, we will often plant more than one clone of a marginal plant like a new palm. Below are two seedlings of the small-seeded European Fan Palm, Chamaerops humilis var. microcarpa. The first shows significant foliage burn, while the second plant, growing nearby shows no damage after 11F.
The hardiest of all Sabal palmetto forms are those from NC’s Bald Head Island. Our plant from there came through the cold unscathed. We expect many local businesses and even homeowners who purchase large trunked forms directly from Florida growers will probably be in for a disappointing spring.
All of our hardy cycads have assumed the straw-color we see every year when the temperatures drop below 18 degrees F. The plants are fine, but we recommend waiting to remove the dead fronds, since doing so now, can cause the new foliage to emerge in the middle of winter, which is never a good idea. April 1 is our target date to remove the fried foliage.
One of the real surprises was the fried foliage of Viburnum ‘Moonlit Lace’, where it was growing in full sun. The same plant growing in shade looks untouched. The stems are fine and the plant should re-sprout fine, but gardeners who grow this in full sun may be disappointed.
This is the coldest temperatures we’ve seen since planting Patrick’s hardy selection, Opuntia microdasys ‘Dripping Springs’. Our clump looks great after the cold. It’s hard to imagine that this clone is so much more winter hardy than any of the other forms of this species that we’ve tried previously and killed at much warmer temperatures. Although we don’t offer this for sales, I’ll remind you of our great prickly pear cactus giveaway at our Summer Open Nursery and Garden in July.
The Mexican Sedum praeltum looks a bit sad, but actually seems to be fine with sound buds up and down the stem. This little-known perennial forms a plant that looks almost exactly like the tender Jade plant, Crassula ovata.
Lastly, our patches of Living Stones, Lithops aucampiae, sailed through 11 degrees F. I wonder if we can ever get all the disinformation on the Internet regarding their tolerance to cold corrected.
One of our favorite palms for the garden is the US native Sabal minor var. louisiana. While it can’t outgrow the Himalayan Trachycarpus fortunei (windmill palm) for speed of developing a trunk, Louisiana palmetto is the most winter hardy of all trunking palms. One of the mysteries is that in the wild, the same population can have both above ground as well as subterranean trunks.
Our garden specimen in the photo below was planted from a 1 qt. pot in 2005. Eventually, Sabal minor var. louisiana will develop an above ground trunk, which on our specimen below is just beginning.
The background on Sabal minor var. louisiana is a botanical mystery. Some taxonomists consider it a valid species, while others consider it variety of the subterranean trunked Sabal minor. Others consider it to be an old hybrid of Sabal minor and either Sabal mexicana or Sabal palmetto. A similar hybrid, Sabal x brazoriensis from near Dallas, had its DNA analyzed several years ago, and was found to be an old hybrid of Sabal minor and a now extinct population of Sabal palmetto.
Sabal sp. ‘Tamaulipas’ from Northern Mexico is another mystery palm in need of some family history work. Thankfully, palm researcher and grad student, Ayress Grinage at Cornell has begun to look at these mystery sabal palms to figure out how they came to be. We, and others have sent material, and now await the results of the paternity test.
Considered the hardiest of the genus Brahea, this rare endemic palm hails from the alkaline Sierra Madre Oriental Mountains in northeastern Mexico, where it’s endangered thanks to the abundance of hungry goats.
Brahea decumbens is ridiculously slow growing. Eventually, the immature green leaves turn a beautiful silvery grey and adorn the 6′ tall x 10′ wide specimen that, with age, develops creeping (decumbent) trunks…much like a blue-leaf Serenoa repens.
We’ve failed three times, loosing each in the winter. Zac mentioned that these need an extremely abusive and neglected environment to survive, so we planted our fourth attempt in our gravel crevice garden where it receives no irrigation. After 3.5 years, it’s actually thriving and looking particularly nice this fall.
If you’ve lived in the deep south…the land of palmetto palm trees, you know that they typically don’t flower until they have at least 5 feet of trunk. Of course, flowering can be sped up by a combination of precocious genes and good growing conditions. Those who have studied Sabal palmetto in the wild have noted that the earliest populations to flower are those from the most northern, naturally-occurring population on North Carolina’s Bald Head Island.
Well, sure enough, our oldest specimen of Sabal palmetto ‘Bald Head’, planted in 1999 finally decided to produce flower this summer, and will hopefully seed. We’ve only had enough plants of this cold hardy form to offer through Plant Delights three times in 36 years. Fingers crossed, we’ll be able to make it available more regularly now. Hardiness Zone 7b and warmer.
Here’s a garden shot at JLBG, using a good bit of gold foliage in addition to flowers. Left to right: Viburnum dentatum ‘Golden Arrow’, Sinningia ‘Amethyst Tears’, Baptisia ‘White Gold’, Canna ‘Tama Tulipa’, Lysimachia nummularia ‘Aurea’ (groundcover), Hibiscus ‘Holy Grail’ (purple), Spirea thunbergii ‘Ogon’, Trachycarpus fortunei (palms).
We love our Mediterranean blue fan palms…one of the coolest palms we can grow outdoors. We’re right on the edge of winter hardiness for Chamaerops humilis var. argentea, so the key is to grow it to a larger size before planting in the ground. We’ve lost a few that we planted too small, and when that planting coincided with a cold winter.
This is a photo taken this January of our oldest clump, now 17 years old. This is a very slow growing palm, so a good bit of patience is required when getting it established. When we do experience single digits F winter temperatures, all of the foliage is burned back, but it re-sprouts from the base in spring. Mediterranean blue fan palm hails from high elevations in the Atlas Mountains of Morocco, where it eventually makes a 15′ tall specimen. In our cold winter climate, we doubt it will ever top 4′ in height. It should be winter hardy from Zone 7b and warmer.
Due to having three consecutive mild winters, with no temperatures below 20 degrees F, we’ve actually been able to get a trunk on our Washingtonia filifera palm. Typically not hardy in our climate, our plant was grown from seed collected from a wild population in Arizona that had experienced 10 degrees F. We’ll see what this winter has in store.
We love plant mysteries, and Sabal ‘Blackburniana’ fits the bill nicely. This pass-along seed strain has been considered by some to be an old hybrid of Sabal minor, while others consider it to be synonymous with Sabal palmetto, yet others consider it to be Sabal domingensis. Whatever it is, our plant is looking quite good in the garden. After growing it, unscathed, since 2008, we finally decided to propagate some for the upcoming Plant Delights catalog. If you know any more historical background about this curiosity, please share.
No, we’re not talking about your favorite football or basketball team, but the amazing blue Mediterranean fan palm. Here’s our oldest (16 year) specimen in our alpine rock garden this week. Chamaerops humilis is a Southern Europe native that’s marginally hardy in our region, but the blue form, know as var. cerifera (or var. argentea). is much more tolerant of our cold winters. If our winter temperatures drop into the single digits F, the foliage dies back to the ground, but quickly rebounds in spring.