No burn on Hibernica

We were thrilled to see how well our Mexican bear grass, Nolina hibernica fared through our recent cold. We had lost this ten times previously, and were close to giving up, but decided to plant this one in a partially shaded site. Previously, we had only planted these in full sun, where they thrived except during cold winters. By growing this partially under shade, it reduces the amount of cooling on cold nights by having a tree canopy nearby. This 8 year old specimen has a way to go before it reaches its potential mature height of 20′. Fingers crossed.

Nolina hibernica ‘La Peña’

So Long Sotols…In the Spirit of Plant Extinction

We’ve long been enamored with the Southwest native genus of slow-growing woody lilies belonging to the genus, Dasylirion. Since the early 1990s, we’ve been growing these, trialing as many species as we could obtain to see how well they adapted to our climate here in the colder, wetter Southeast.

Image of Dasylirion wheeleri in situ, Payson, Arizona
Dasylirion wheeleri in situ, Payson, Arizona

So, far, we have grown 16 of the 21 recognized species and succeeded with 12. We found four unable to survive our coldest winters, including Dasylirion durangensis, Dasylirion longissimum, Dasylirion lucidum, Dasylirion sereke.

The five species we have yet to try in the garden are Dasylirion graminifolium, Dasylirion longistylum, Dasylirion micropterum, Dasylirion palaciosii, and Dasylirion simplex. We have seed planted of both Dasylirion graminfolium and micropterum, so those will be next in line for our in ground trials. That leaves us still searching for seed of the final three.

Sotols, like agaves, are members of the Asparagus family. They are becoming wildly popular, but not because of gardeners. Instead, their popularity is driven by those who are driven by a need/desire to imbibe alcoholic spirits. First, there was Mescal, a Mexican drink made from one of a number of different agave species, depending on what grew in proximity to each village. Of the Mescals, the most popular is Tequilla, which is made from a single species, Agave tequiliana.

Now, Sotol alcohol has joined the ranks of the “hot new spirits”. Made from agave’s cousin, plants of the genus Dasylirion, Sotol is rapidly becoming the new “flavor of the month”. Sotol alcohol certainly isn’t new, and if you regularly travel south of “the wall” you probably already know that Sotol is the state drink of Mexican states Chihuahua, Coahuila, and Durango.

Not so long ago, Sotol alcohol had a history that somewhat parallels moonshine in the Southeast US. For years, Sotol alcohol was illegal and subject to government raids, during which master sotoleros were punished or imprisoned. During the US prohibition of the 1920s, Sotol sales in the US skyrocketed, but soon after its repeal, Sotol sales plummeted back into obscurity. Now, with not only social acceptance, but a wide wide embrace of virtually anything that can be used to produce alcohol, Sotol has been mainstreamed with the assistance of the Mexican government and willing marketers.

Most agaves for Tequila production are now commercially grown in massive farms, and most plants are now produced from tissue culture for a more consistent yield and to take pressure off wild popuations. Even under ideal farming conditions, it take 5-7 years to get an agave large enough to harvest for tequilla production. With dasylirions, the same process takes at least 12-15 years according to Sotol marketers. Based on our 30 years of work with the genus, I’d say the time involved is more likely 24-30 years, even in a high rainfall climate like ours.

I’m not aware of many farm operations that can afford to grow a plant for that long before expecting a return on investment. This means that poaching of plants from the wild is very likely to increase. With such a low rate of return, i.e. 1 pint of liquor for each plant harvested, I can’t see the plants coming out on the good end of this industry. While making alcohol from dasylirions isn’t new, it’s been done on a very limited scale in Mexico, prior to word spreading around the world via social media.

Reportedly Sotol spirits taste quite different based on the species used, and whether it’s from an exceptionally dry region or an area with better rainfall. Sotol conniseurs describe the tastes as being a bit like menthol or pine/mushrooms if the plants are grown well hydrated, while those from drier regions taste more like leather. To quote Dave Barry, “I’m not making this up!” And this sounds appealing to who???

Supposedly, the spirit producers are cutting off the wild dasylirions and leaving the bases to resprout, but I’ve got my doubts about how well that works. Assuming the cut dasylirion does resprout, there will be a decade of lost seed production, so plant populations in the wild are almost certain to decline. I’m left to wonder if we really are so desperate for a new taste in alcohol that we are willing to sacrifice another genus of plants in the process.

In celebration of these amazing plants, here are photos of those we have grown in our ex-situ conservation gardens at JLBG.

Dasylirion acrotrichum, named in 1843, is native to Mexico’s Chihuahuan desert. Of the seven plants we planted, only one survived, which is now over 20 years old. This widespread sotol, which occurs on igneous soils, has been split by various authors into several subspecies. Undoubtedly, winter hardiness varies based on the seed procurement location. At maturity, the trunks can reach 5′ tall.

Image of Dasylirion acrotrichum
Dasylirion acrotrichum

Dasylirion berlandieri, named after French/Mexican naturalist, Jean-Louis Berlandier (1803-1851), was first published in 1879. Native to steep rocky hillsides in Tamaulipas and Nuevo Leon in Northeastern Mexico, it’s one of the largest species in the genus in width, but with a trunk that never exceeds 1′ in height. Below is our plant in bud. Unlike agaves, dasylirion rosettes do not die after flowering.

Dasylirion berlandieri

Below is a fully open flower spike, which is abuzz with a large number of bees

Dasylirion berlandieri in full flower

Dasylirion cedrosanum, first documented in 1911, hails from 3,000′ – 6,000′ elevation on rocky, gypsum-laced hillsides in the Sierra Madre Occidental mountain range. They are restricted to the Mexican states of Chihuhua, Coahuilla, and Durango. At maturity, they produce a 3′ tall trunk.

Dasylirion cedrosanum

Dasylirion durangensis is another species first described in 1911, which hails from the dry alkaline/limestone-gypsum deserts of Coahuila, Chihuahua, Durango, and Zacatecas. In parts of its range, it interbreeds with Dasylirion wheeleri. We flowered this prior to losing it during a particularly cold winter. Below is our Obit photo.

Dasylirion durangensis

Dasylirion gentry was only published as a species in 1998. It has a very limited range between 3,500′ – 4,000′ in Sonora, Mexico, where it grows on rocky slopes in openings of pine/oak woodlands.

Dasylirion gentryi

The inflorescense of Dasylirion gentryi is one of the most spectacular we’ve ever seen.

Dasylirion gentryi bloom spike

Dasylirion glaucophyllum is a species whose discovery dates back to 1858. It can be found naturally, only in Sonora, Mexico, growing on rocky hillsides at elevations to almost 8,000′. At maturity, trunks measure up to 6′ in height.

Dasylirion glaucophyllum

Dasylirion leiophyllum, published in 1911, only grows north of Mexican border in Texas and New Mexico. Based on where it grows, it should be one of the most winter hardy sotol species. The first photo is at JLBG, and the second in situ at 5,400′ elevation. The second image is from the late plantsman, David Salman, of a Zone 5 population he discovered and shared seed with us just prior to his untimely death. Plant Delights is currently offering this as Dasylirion leiophyllum ‘Chaves’.

Dasylirion leiophyllum – in winter at JLBG
Dasylirion leiophyllum ‘Chaves’ in situ at 5,400′ elevation

Dasylirion miquihuanense, only described in 1998, hails from Tamaulipas and Nuevo Leon in Northeastern Mexico. Also occurring on rocky slopes, this sotol is one of the tallest species, producing massive 8′ tall trunks. We have succeeded long term with only 2 of 8 specimens we planted.

Dasylirion miquihuanense

Dasylirion parryanum, published in that banner year of 1911, hails from up to 8,000′ elevation in the San Luis Potosi State in Northern Mexico, where it produces 3′ tall trunks.

Dasylirion parryanum

Dasylirion quadrangulatum (1879) hails from the Southern (warmer) end of Tamaulipas and Nuevo Leon. It is much too tender for us to grow in the open here in Zone 7b, but we’ve kept it alive for a couple of decades by siting it in a microclimate adjacent to a brick wall house foundation. It is one of only two species lacking leaf spines. With great age, it produces trunks to 9′ in height.

Dasylirion quadrangulatum

Dasylirion serratifolium, first described in 1838, is from Oaxaca, Mexico, where is grows on rocky, alkaline hillsides to 6,600′ elevation. The location and elevation means it really shouldn’t survive our winter. That said, our only remaining specimen below is now 20 years old, but is still far from reaching the 6′ tall trunk height it does in the wild.

Dasylirion serratifolium

Dasylirion texanum (1850) is another very winter hardy species, found on rocky slopes, ranging from Central Texas into the mountains of Northern Mexico. It is one of the shortest species, with a trunk that doesn’t exceed 1′ tall.

Dasylirion texanum

Dasylirion wheeleri, first documented in 1878, ranges from Texas, Arizona, and New Mexico south into the mountains of Northern Mexico. It matures at 6′ tall, and in situ, can be found in both grasslands as well as openings in pine/oak forests. It is another of the most cold hardy species.

Dasylirion wheeleri

An old clump we planted years ago in flower is quite remarkable.

Dasylirion wheeleri in flower

We hope you’ll limit your consumption of Sotol as a drink and instead join us in becoming an ex-situ conservation garden for this amazing genus of plants.

Mr. Russell’s Mahonia

Mahonias have long been garden staples, but few people have ever seen or tried the rare Mahonia russellii. Discovered in 1984 in Vera Cruz, Mexico by the UK’s James Russell, this member of the “paniculate” clan of mahonias is more closely related to other Southern Mexico and Central American species, than anything most of us grow in our gardens. In other words, there is no way we should be able to grow this outdoors.

Below is our specimen flowering in the garden just prior to our low of 11 degrees F and three consecutive nights in the teens. Surprisingly, it escaped with what appears to be minor foliar damage, and of course a loss of the floral show.

Image of Mahonia russellii
Mahonia russellii

Green Goblet

Looking great in the garden this week is Agave x pseudoferox ‘Green Goblet’. This 1996 introduction from the former Yucca Do Nursery is one they found in Mexico and brought back as a single pup. Our original plant flowered in 2011 after 11 years in the ground, so this specimen has re-grown from one of the remaining small pups. Since we’re now at 11 years since last flowering, we’re preparing for a new blessed event. Since we can usually tell by now if it’s expecting, which it is not, the odds are pretty good for a 2024 flowering. Plant Delights Nursery will be offering A. ‘Green Goblet’ for sale in 2023.

An 11 year old plant of Agave x pseudoferox 'Green Goblet'.
Agave x pseudoferox ‘Green Goblet’

Excelsior…Fit for a King

Here’s a new photo of Agave parryi ssp. huachucensis ‘Excelsior’ from our garden this week. We typically don’t have many variegated century plants that will survive our winters, but this is one of the exceptions. This superb clone was first introduced in 1967 from a small California nursery by the same name. Protection from excess winter moisture and exceptional drainage is always the key in cold, wet winter climates. This particular planting is under a roof overhang. Hardiness zone 7b to 9b.

Agave parryi ‘Excelsior’

Poli wants a Freda

A couple of years ago, we made bi-generic crosses of the North American Manfreda maculosa and the naturally occurring hybrid Mexican tuberose, Polianthes x bundrantii ‘Mexican Firecracker’. These fascinating plants were still in full flower prior to our first hard freeze in the last few days. These are images of our top three clones, which we refer to as x Polifreda. Because we used the non-fragrant tuberose species, there is no noticeable aroma, but we opted for a much more diverse flower color range instead.

Hopefully, next year, we can use these to cross with agaves to create a new series of xHanseras. Pollen has been gathered and stored in the refrigerator in case bloom times don’t coincide next year.

x Polifreda - salmon in the trial garden
x Polifreda – salmon
x Polifreda - peachy/yellow in the trial garden
x Polifreda – peachy/yellow
Close up of x Polifreda - yellow/orange bicolor
x Polifreda – yellow/orange bicolor

The Un-Buddleia

Most folks have grown butterfly bushes in the genus buddleia, yet few garden visitors recognize this fascinating species from our 1994 botanizing trip to Northern Mexico. I should add that most buddleias on the market are developed from the Asian species, and virtually none from the less colorful North American species.

Buddleia cordata ssp. tomentella grows in rocky, bone-dry hillsides in the mountains of Northern Mexico near the town of Los Lirios at 7,000′ elevation. I was only able to find a single seed, but fortunately, it sprouted, and 28 years later, this amazing specimen is the result.

One of the cool things about Buddleia cordata ssp. tomentella is the insanely fragrant flowers, which start for us in early fall, and continue all winter…a trait you won’t find in any other temperate shrub of which we’re aware. As you can imagine, it is awash with an array of pollinator insects The flower color is a dusty white, so this will never be a plant that will make it to the shelves of your favorite box store. That said, it’s a plant we wouldn’t be without in our garden.

Image of Buddleia cordata ssp. tomentella blooming in the garden.
Buddleia cordata ssp. tomentella

Decumbent Brahea

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.

Brahea decumbens in the crevice garden
Brahea decumbens

Planting for Halloween

With enough plant diversity, there are all kind of possibilities to target floral interest for certain seasons or even holidays. Since the Halloween season is just past, here are a couple of seasonal favorites.

If there’s ever been a plant designed for the Halloween holidays, Cuphea micropetala has to be near the top of the list. This amazing perennial hails from the subtropical regions of Central and Southwestern Mexico. Below is our plant on Halloween this year. Flowering for us typically starts in early October. Despite its warm origins, it’s a reliable perennial here in Zone 7b.

Cuphea micropetala, a great Halloween plant
Cuphea micropetala

The other can’t miss seasonal favorite, is our 2005 introduction of Gladiolus ‘Halloweenie’. This crazy gladiolus from South Africa, skips the typical spring flowering season, and instead, starts flowering the week of Halloween.

Gladiolus dalenii 'Halloweenie'
Gladiolus dalenii ‘Halloweenie’

Agave ‘Prince of Whales’

Our 2016 century plant hybrid is looking quite lovely in the garden this month. This plant, which we named Agave x victorifolia ‘Prince of Whales’, is a hybrid of the Whale’s tongue century plant, Agave ovatifolia (male parent), and the Queen Victoria century plant, Agave victoriae-reginae (female parent).

Since both parents are non-offsetting, this means that the offspring will grow to maturity, flower, then die. Consequently, in order to be able to propagate and share, we will have to drill out the central core of the plant to trick in to offset. While this ruins the appearance of the original, it’s the only way for this to ever be shared and preserved. This plant has been in the ground since 2018, so we expect to have another eight years (guessing) prior to flowering. Consequently, so we’ll probably gamble on waiting a few more years before performing surgery. Winter hardiness is Zone 7b-10b.

Agave x victorifolia Prince of Whales
Agave x victorifolia ‘Prince of Whales’

Below is a photo of both parents.

Agave ovatifolia
Agave ovatifolia
Agave victoriae-reginae
Agave victoriae-reginae

Shadow Dancer

Looking lovely today is the amazing Agave x romanii ‘Shadow Dancer’. This fascinating agave is a man-made hybrid between two Mexican species, Agave filifera and Agave mitis. Not only is it a hybrid, but this selection has a fascinating variegation pattern that’s not seen on any other century plant. The new growth emerges ghostly cream with a muted green border. As the leaves age, they green disappears and the leaves become pure parchment white. Despite the seeming lack of chlorophyll, Agave ‘Shadow Dancer’ has amazingly good vigor and doesn’t burn in full sun. This has potential winter hardiness for Zones 8b and south, but needs more trialing to know for sure. In other climates, it’s a great container specimen.

Agave x romanii 'Shadow Dancer' potted on the deck
Agave x romanii ‘Shadow Dancer’

Bearing Flowers

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.

Nolina nelsonii

Jammin’ Jame

Salvia regla ‘Jame’ (pronounced Haam-hey) is looking so wonderful this time of year. This amazing North American native (US/Mexico) was originally shared back in 2000, by the late Salvia guru, Rich Dufresne. It has adorned our gardens every year since with these amazing fall shows. Hardiness is Zone 7b and warmer.

Saliva regla ‘Jame’

Tarahumara Oak

One of our prize plants in the garden is the Tarahumara Oak, Quercus tarahumara. This truly odd oak is native to Northern Mexico, where it resides in the Sierra Madre Occidental Mountain range in the Mexican states of ChihuahuaSonoraDurango, and Sinaloa.

In cultivation, Quercus tarahumara is extremely rare and of high conservation value. It seems that there are only a few plants existing in cultivation, although a few others in collections turned out to be hybrids. So far, temperatures in the upper single digits haven’t posed a winter hardiness problem.

Quercus tarahumara is named after the Tarahumara Indians, who live in the botanically rich region, popularly known as Copper Canyon.

Quercus tarahumara

The foliage is ridiculously thick and feels like hard plastic. Turned upside down, the leaves function quite well as a drinking cup or small sink.

Quercus tarahumara

Pale Puma

We love the winter hardy spiderworts, and Tradescantia ‘Pale Puma’ is one of our favorites. This hybrid of two northern Mexican species, T. pallida x sillamontana forms a lovely compact deciduous groundcover. Here it is in the garden this week, colored nicely and awaiting the first frost, which will send it into dormancy. In colder climates, it makes a great hanging basket plant.