We all love the color of leaves in fall…at least until they need to be raked. Here are a few that we enjoyed at JLBG recently.
Acer triflorum ‘Aureum’ really put on a lovely show with leaves that held on quite a while. It also colored later than most other maples.
Euonymus carnosus was quite stunning, although the effect really didn’t show up as well in the photo.
Parrotia persica is one of the last deciduous trees to color and drop in our garden. The typical color is yellow, although I’ve seem some pretty amazing red-leaf forms as well. We have not noticed much in the way of color on Parrotia persica ‘Vanessa’.
Parrotia subaequalis is the star of the genus when it comes to fall foliage, which is a brilliant purple red.
Although our row of Metasequoia ‘Ogon’ turn brown in fall, it’s still an amazing show. These are the oldest plantings of this cultivar in the US.
Gardeners typically curse fall leaf drop, but ginkgo trees often get a pass, not only because the golden fall leaves look so great on the tree, but they also look great on the ground, not displaying the disheveled look of other larger tree leaves. Here’s our ginkgo tree, planted just in front of our office, that’s been putting on quite a show for the last few weeks.
Despite what most folks think, the genus Ginkgo is indeed a North American native, but to understand that, requires a bandwidth that many native plant purists simply don’t have. Native is not a place in location, it is only a place in time. The first Ginkgos date back to the lower Jurassic period about 190 million years ago, when the genus was born in Mongolia. From there, it migrated around the world, based on dramatic climate change, with fossils found from what is now the UK to the US (Oregon to North Dakota).
Ginkgos continued to diversify through the Cretaceous period (65-145 million years ago), when they reached their maximum distribution, with 5-6 species currently recognized. By the Paleocene (56-66 million years ago), all of the species but one had gone extinct. Although that remaining species is known as Ginkgo adiantoides, it is almost identical to today’s Ginkgo biloba.
During the Oligocene (23-34 million years ago), Ginkgos moved south from their more northerly range, with the genus completely disappearing from North America around 7 million years ago. According to the fossil records, Ginkgos subsequently disappeared from Europe around 2.5 million years ago. The only vestiges of the genus that remained, holed up in three distinct refugia (botanical hideouts) in China until humans began to spread them out again and re-populate the rest of the now Ginkgo-less world. They returned to the Flora of both North America and Europe in the 1700s.
For those who want to dive deeper into the Ginkgo story, here is a link and another.
One of the last plant exploration trips the late plantsman Alan Galloway made, was to Majorca, Spain. Alan was so excited to return home with some special selections of the fall-flowering Arum pictum, which typically has solid green foliage…except on Majorca. This beautiful form is known by collectors as Arum pictum var. sagittitifolium, although the name isn’t considered valid due to the natural variability in leaf patterns. This is Alan’s favorite form from his trip, to which we added the cutlivar name, A. pictum ‘King James’. It seems that back when Majorca had kings (thirteenth and fourteenth century), before its merger with Spain, they had a propensity for naming most of them, James.
I’ve never been a huge fan of nandinas in the garden. I find the more typical forms very difficult to integrate from a design perspective, and I find the popular Nandina ‘Firepower’ to be near the top of the list of most grotesquely ugly plants used in American landscapes. Yes, it’s colorful, but the plant lacks any grace, and has the form of a pile of wet red Kleenex.
Of the older cultivars, I like Nandina ‘Harbor Dwarf’, with it’s low spreading form, but the paucity of fruit keeps most people from planting it. The only downside for us is that it spreads to cover a very large footprint, so can choke out other nearby plants. We continue to trial all of the new nandina introductions to see if anything strikes our fancy.
My favorite member of the genus, which I first met at the JC Raulston Arboretum back in the 1980s, is Nandina domestica ‘Filamentosa’. This cutleaf, slow-growing, non-fruiting selection from Japan is often marketed under the trade name San Gabriel. It adds a distinctly Japanese flavor to the landscape, which is why we planted a mass in our new Japanese garden. Here is a photo from this week with it’s lovely rosy winter color. Winter hardiness is Zone 6b-9a.
Late summer and fall are a great time to enjoy the plumes of our US native ornamental grass, Panicum virgatum. Here are two photos from the garden this week. The first is one of my favorites, the giant Panicum ‘Cloud 9’…an introduction from Maryland’s defunct Bluemount Nursery. Below this is a new dwarf, blue-foliage introduction for 2022, from Walters Gardens, Panicum ‘Niagara Falls’. It has proven exceptional in our trials and will appear in the January Plant Delights Nursery catalog.