Rooting for Buckeyes

Here are a few of the many buckeyes that are looking good at JLBG this spring.

Aesculus pavia is native from Illinois south to Texas and east to Florida. Hardiness is Zone 4-8.

Aesculus pavia

The European Aesculus hippocastanum has thrived for us, despite most sources claiming we are too hot in the summer. Aesculus ‘Hampton Court Gold’ emerges with ghostly yellow foliage for an amazing spring show.

Aesculus hippocastanum ‘Hampton Court Gold’

Aesculus x carnea is a hybrid of the European Aesculus hippocastanum and the American Aesculus pavia. This cross was first discovered in Europe in 1812. It is quite stunning in our garden as you can see. Hardiness is Zone 5-8.

Aesculus x carnea ‘Variegata’

The dwarf form of Aesculus glabra only occurs in a small region of Northern Alabama/Georgia. Mature size is 5-6′ tall. Hardiness is Zone 5-9.

Aesculus glabra var. nana

Aesculus sylvatica is one of our oldest buckeye specimens in the garden. This species is native from Virginia to Alabama. Hardiness is Zone 6b-8b.

Aesculus sylvatica

Aesculus sylvatica ‘Sylvan Glow’ is Jeremy Schmidt’s discovery of an amazing seedling of Aesculus sylvatica that emerges rosy red, then changes to orange, before aging to green for the summer. When it gets a bit larger, we will try to propagate this so we can share.

Aesculus sylvatica ‘Sylvan Glow’

Golden Sunshine

Even when the sun isn’t out, the golden willow, Salix sachalinensis ‘Golden Sunshine’ provides a bright spot in the garden. We love this amazing tree. I see quite a few sources who list this on-line as maturing at 18′ tall x 7′ wide. Well, that’s not quite accurate. The five year old specimen pictured below is now 25′ tall x 25′ wide. Growth is much faster in moist, rich soils, but it seems someone needs to trade in their tape measure.

Salix sachalinensis ‘Golden Sunshine’ PP 19,370

David’s Tree

We’ll certainly remember 2022 for many reasons, but a highlight is the first flowering of our Davidia involucrata ‘Sonoma’. This incredible tree was named for French missionary and naturalist, Armand “Pere” David (1826-1900), who first discovered the tree in its native China.

Like dogwoods, what we think of as flowers are actually bracts, the effect is that of the tree in flower is like a dogwood on steroids. Interesting, davidia is in the black gum family, Nyssaceae, and although this tree is not common, it has acquired the common name of dove tree.

We’ve learned a bit about what davidia likes, having killed five plants since first trying it in 2002. Full sun is not ideal, as is deep shade. Our original plant, which as been in the ground since 2002 has yet to flower. The plant of Davidia ‘Sonoma’, which flowered this year, was planted in 2014, and is thriving in light shade/part sun.

Hail to Halesia

Flowering in our parking lot now is the beautiful Halesia diptera var. magniflora, better known as big-flowered two-wing Silverbell. Native from Georgia across to Texas, this beautiful small tree can be found in low moist woodlands. That said, it thrives in average to dry garden conditions.

The variety “magniflora’ is distinguished from the more northern Halesia diptera var. diptera in that the gulf coast form has much larger flowers. This is our collection from Wilcox County, Alabama, where the foliage is much wider than what is typically seen in this taxa. Plants mature at around 20′ in height. Hardiness is Zone 5-8.

Halesia diptera var. magniflora ‘Pine Apple’

A Forest of Pink

Magnolia ‘Forest’s Pink’ put on a splendid show this year in early to mid-March. Sold as a cultivar of the Chinese Magnolia denudata, some magnolia experts insist that it’s actually a hybrid, due to the intensity of the pink color as well as the form of the plant.

Magnolia ‘Forest’s Pink’ originated as an introduction from Treseder’s Nursery in Cornwall, England, who propagated and named it from an original introduction from China by Scottish botanist, George Forrest (1873 – 1932), that was growing at England’s Caerhays Castle.

Magnolia denudata, a typically white-flowered species, native to Central China, has been cultivated around Buddhist monasteries since 618 AD…in other words, nearly 1,500 years. Another long-cultivated Chinese native magnolia with pink flowers and an overlapping native range is Magnolia liliiflora. The commonly known hybrids of the two species are known as the Magnolia x soulangeana hybrids. Since plant explorer George Forest was known to collect both in the wild as well in cultivated areas, it is quite probably that the magnolia that bears his name is not pure Magnolia denudata, but actually a Magnolia x soulangeana hybrid. Looks like someone will need to do some DNA work to sort out this nomenclatural tussle.

Whatever you want to call it, our 25 year-old specimen of Magnolia ‘Forest’s Pink’ was rather stunning this March. Thankfully, the flowering was mostly complete before our mid-March freeze of 23 degrees F.

The Elusive Red Witch Hazel

Flowering this week at JLBG is the amazing cherry red Hamamelis japonica ‘Tsukubana-kurenai’, also known as Shibamichi’s Red witch hazel. This gem was selected by legendary Japanese nurseryman, Akira Shibamichi, who also introduced Metasequoia ‘Ogon’. We were blessed to have Mr. Shibamichi visit JLBG back in the 1990s.

Beautiful Madness

I borrowed the title from our good friend Jim Dodson’s book for this post about Ulmus parviflora ‘Golden Rey’. One of the most admired trees in our garden is our specimen of Gold-leaf lacebark elm. The bark, as you can see below is absolutely fabulous both in winter and summer.

Ulmus parviflora ‘Golden Rey’

The problem is that lacebark elm is a notorious seed producer, and in our garden, it seems like every one germinates. Our love/hate relationship with this species has so far resulted in the removal of four different mature cultivars from our garden so far.

Here’s where genetic engineering (GE) could actually help. Notice, we are using the term GE, as compared to the incorrectly used GMO. All, plants, unless they come directly from the wild, are genetically modified organisms (GMO). Humans would cease to exist as we know them without GMO’s, so, please try to use the correct terminology. What people are crusading against in food crops is actually genetic engineering (GE). Hoping down now from my soapbox.

It’s actually quite easy to sterilize a plant, using one of the genetic engineering tools known as CRISPR. Just think of this GE surgery as a horticultural vascectomy…a couple of snips and you’re done making babies. It will be interesting to see if public sentiment for non-edible crops allows genetic engineers to solve such problems with making some amazing plants like the widely planted lacebark elm more palatable to gardeners who are concerned about its potentially invasive tendencies.

Grapefruit time in the garden

We love December, since that’s when the grapefruits start to rain down from our xCitroncitrus ‘Dustan’ tree at JLBG. Few people who come to the garden actually look up enough to notice this fascinating plant. xCitroncitrus ‘Dunstan’ is a bigeneric hybrid between the hardy trifoliate orange, Poncirus trifoliata and a grapefruit. The result is a winter hardy fruit that’s pretty darn close in size, taste, and appearance to a grapefruit. To be technically correct, the fruit is known as a Citrumelo. Whatever you want to call it, it’s pretty darn cool to be harvesting hardy citrus here in Zone 7b. Last year, we harvested over 3 dozen fruit off our single tree.

Honey, I shrunk the River Birch

I remember falling in love with the dwarf river birch, Betula nigra ‘Little King’, back around 1990 when it was first planted at the JC Raulston Arboretum in Raleigh, NC. This amazing compact selection originated in the late 1970s at King Nursery in Oswego, Illinois, and starting in 1991, was adopted and formally marketed through the Chicagoland Grows plant introduction program.

After 20 years, the original plant in Illinois was only 10′ tall, but the 30 year old specimen at the JC Raulston Arboretum has now reached 30′ tall x 30′ wide So, while it is much slower growing, it’s not exactly a true dwarf. Most estimates conclude that Betula ‘Little King’ will grow about 1/3 to 1/4 the speed and size of the typical species, making it a much better choice around most smaller homes. That said, we love the compact, dense habit and have recently planted this specimen around our home on the JLBG property. Hardiness is Zone 4-9.

Information you can trust

With over 60% of retail plants now purchased at the box stores, we wonder if most consumers know you can’t trust much if anything you read on a label at a mass marketer. Our most recent example is this tag on an Illicium parviflorum at our local Lowes. I particularly love the common name, Japanese Anise. Unfortunately, Illicium parviflorum is native only to Florida…quite a few miles from Japan.

The tag mentions full sun, which Illicium parviflorum certainly tolerates, but in the wild, it grows naturally in moist woodlands.

Then, there is the note about cool temperatures and warm soil promotes root growth. Well, warm soil does promote root growth for some plants, but not for all. Wouldn’t the soil have been warmer in mid-summer than now? Just wondering…

And, if that wasn’t enough, our staff taxonomist, Zac Hill spotted this tag for our native bald cypress, Taxodium distichum at a different Lowes store. The problem is that the plant is actually a Chinese Dawn Redwood, Metasequoia instead of a Taxodium. I wonder if they thought…”what the hell, those dumb consumers will never know the difference.”. After all, it’s just another little green lie. As Anita likes to say, ‘The way you do one thing is the way you do everything.”

Blonde Envy and More

I can’t speak to the truth that blondes have more fun, but on behalf of gardeners who grow blondes (gold leaf plants), we certainly have more fun when they’re around. One of our horticultural holy grails has always been a gold leaf elderberry we can actually grow. The horticultural market is dominated by northern cold climate selections of colored-leaf elderberries, which refuse to survive our hot, humid summers.

I can’t tell you how excited we were a couple of years ago to learn of a Keith Mearns discovery of a wild elderberry near Columbia, SC with beautiful golden foliage, Sambucus canadensis ‘Blonde Envy’. Although it took us a while to track one down (Keith says that less than a dozen exist in the world currently), it is now performing beautifully in a prize spot at JLBG. We’ve turned our Plant Delights propagators loose in the hope we can have enough to share in the 2023 Plant Delights spring catalog.

Just prior to the pandemic, we were plant collecting in UK nurseries, and made a stop at the always amazing Cotswold Garden Flowers. Founder Bob Brown’s son, Edmund, had taken up elderberry breeding, and now held the National Sambucus collection. We were able to bring back a couple of his complex hybrid introductions to trial, and to our shock, both are thriving in our summers. Here is a photo of our 2 year-old clump of Sambucus ‘Chocolate Marzipan’ in the garden. Finally, sambucus envy will be over for southern gardeners.

Vilmorin’s Oak

Outside of the nerdy members of the International Oak Society, few gardeners have ever heard of Quercus x vilmoriniana. This spectacular oak is a hybrid between the Asian Quercus dentata and the European Quercus petraea. Quercus x vilmoriniana has been known in European gardens since 1894, but is rarely seen in US gardens. The hybrid is named for the late French botanist Maurice Leveque de Vilmorin.

Our 20′ tall specimen at JLBG was planted in 2012 and has developed not only superb foliage, but splendid deeply-fissured bark. There is an old specimen at Cornell in NY, so it shows good cold tolerance in addition to loving our hot, sweaty summers. We have sown acorns from our plant, and if they grow, we will make this available though the Southeastern Plant Symposium Rare Plant Auction in June.

Orangeola

Sounding more like a soft drink/crayon combination, Orangeola is actually a stunning selection of weeping, dissected, purple-leaf Japanese maple. Our oldest specimen at JLBG is now 27 years old, and measures 5′ tall x 12′ wide…sorry that size doesn’t really match what you’ll find on-line. We think it’s one of the most handsome clones we grow.