I HAVE A FOLIAGE THING, probably more so than for flowers, so no surprise that a genus of trees I’m particularly passionate about is Acer, or maple, and especially the so-called Japanese maples—which do technically flower, of course, but not in the obvious way a magnolia or dogwood might. I invited Adam Wheeler, Broken Arrow Nursery’s propagation and plant development manager, to my public-radio podcast to talk maples.
Adam and I talked about not just the Japanese types, but also other garden-sized maples for adding interest in every season and garden situation–in pots or the high shade of woodland gardens, to full-sun locations.
my maple q&a with adam wheeler
Q. When I was at Broken Arrow recently, there were many choice things to look at—but I kept noticing the maples you offer, particularly. How many do you grow?
A. In the collection at the nursery, I suspect we have 150 or 200 different maples, and really that’s the tip of the iceberg with this genus.
Q. There are a lot of native American maple species, and Asia has a lot of beauties, too.
A. Our collection spans the full diversity, yes.
Q. So what’s a “Japanese maple”?
A. Loosely “Japanese maple” would be any maple native to Japan, but really what they’re talking about is Acer palmatum, or Acer japonicum, those two species of maples.
Q. There is a third species that gets included in there in listings—the one with the hardest name to pronounce.
A. Yes, Acer shirasawanum also gets lumped in.
Q. And they don’t all look the same. As much as I would say, “I love Japanese maples,” there are some that I don’t love, and some that I really, really do.
A. Among those species, there really is a lot of diversity as far as varieties and cultivars. All those species tend to be small trees on their own, and will get to be about 15-25 feet tall.
But with the diversity of cultivars, you really can find one that will fit just about any garden space: from super dwarf forms on up to weeping forms and very upright forms, as well as just the standard tree forms. We try to carry a diversity of forms and habits to fit different garden applications people are looking for.
There’s also a lot of diversity with the foliage color and texture.
Q. There really is—and that’s what you see at first, if you’re buying a young plant in a container, a smallish plant, like many of us start with, since they can get pricey otherwise. The foliage is what strikes you first.
A. We have standard green-leaf forms, and then some exceptional gold-leaf forms…
Q. …some of my favorites fit in there—you know me with gold leaves!
A. The full-moon maple, Acer shirasawanum, is one of the best golden-leaf forms you can grow, a spectacular 15-foot tree whose foliage just glows [photo above].
Q. It’s not lacy or fine-textured as some, but bolder. And on the other extreme of color?
A. We have dark purples as well. The classic purple-leaf form is Acer palmatum ‘Bloodgood,’ a wonderful, durable, 20-foot tall tree with wine-purple foliage that really stands out.
Q. In the North it was almost synonymous with “Japanese maple.” If you went to a garden center and asked for one, ‘Bloodgood’ is what you were directed to. It was hardy, and even near where I garden, you see old trees that have endured many winters.
A. It’s kind of the benchmark for hardiness for Japanese maples, a solid Zone 5 plant (though not a cold Zone 5 plant)—which is kind of the upper end of hardiness for this group.
Q. And I have one or two varieties whose leaves I wouldn’t call purple, but reddish, perhaps—more the warm side of red than wine-colored?
A. Cultivars with that kind of coloration are on a spectrum, and their color also changes through the season. So a lot have the richest color saturation in the spring and it evolves as the season progresses.
Q. Backtracking to hardiness again: The first time I adopted a “Japanese maple,” I wanted something hardy to grow in the ground, but not something with that purple leaf, like ‘Bloodgood.’ A nursery near me, Windy Hill, suggested a Korean species.
A. The Korean maple, Acer pseudosieboldianum, is a wonderful option, especially for folks that can’t grow Acer palmatum, because it’s a full zone more cold-tolerant. It will stretch into Zone 4 conditions. It gets fantastic scarlet and orange fall color [photo above].
Q. And in spring, when it leafs out, it’s such a fresh light green. Beautiful.
A. It’s a wonderful plant, and underutilized.
Q. So you said there’s a Japanese maple for every situation, from pots to full-on out in the garden as a 20-foot tree. What about the best container types?
A. I have a couple of personal favorites. One is ‘Mikawa Yatsubusa’ [photo above right] a very dwarf plant with leaves that are a nice, fresh green and very close to one another. The plants only grow about 2 inches a year, and ultimately get a very sculpted, airy, open framework. In a large container, they look wonderful, and top out at about 5 or 6 feet tall. It reminds me of shingles on a roof, the way the leaves stack up on the stem.
I’m also a big fan of one called ‘Shaina’ [photo above left], a purple-leaf selection with an oval framework, and holds its color saturation through the season. It only gets to be about 4 or 5 feet tall ultimately.
Q. These would be able to be in pots for a good long time.
A. When you grow them in containers, it slows down the growth rate just a little bit, so they often stay more compact for a longer period of time.
Q. I would definitely second that idea, because as you know, I have tortured some of the larger ones—like the full-moon maple—in very large pots for maybe eight or nine years. And I say “torture,” semi-kiddingly, but it’s maybe one-third the height it would be in the ground, because I’m restricting the roots. You do need to repot and root-prune, yes?
A. Root-pruning will help the plant stay happier for a longer time in a pot. Typically, when I do it at home, I do it first thing in the spring, before new growth develops. I pop them out of the containers, inspect the roots, and prune off any girdling or spiraling roots that have developed, and kind of rough up the rest a bit. That’s when I’ll make the decision to put it back into the same container, or into a slightly larger one.
Q. The problem with doing what I did—putting the bigger-growing varieties in pots [which I store in my unheated barn, dormant, all winter]—is that now I’ve moved them up a number of times and reached the largest pot possible. So maybe I need to hand them down to someone a Zone south of me to adopt, who can put them in the ground. [Laughter.]
So what are the basic needs of Japanese maples—how do they grow in nature?
A. They’re actually very tolerant plants. They prefer a slightly acidic soil, but they’re adaptable to varied conditions once established. You want to try to avoid a lot of drought stress, because the foliage can get leaf scorch—dried out. You’re after an evenly moist situation, but not water-logged.
They grow great in full sun or pretty deep shade, but the only thing about shade that I caution people about: You lose some of the fall-color excitement. You won’t get the prominent reds and scarlets, but more yellows in shade.
Q. We didn’t talk much about leaf texture—but are the most delicate, lacey ones actually delicate, or as tough as the others, despite their appearance?
A. The lace-leaf ones can be as durable or more durable than the standard forms. They’re wonderful garden plants. One of my favorites is called ‘Koto No Ito,’ a green-leaf form with heavily dissected, finely lobed leaves that are a rich green color. It’s a wonderful contrast plant in a mixed border, or as a standalone specimen. It gets maybe 12-15 feet tall ultimately, and I love it in containers as well.
Q. Is it Zone 6, too?
A. It’s probably a Zone 5 plant; I’m in a warm Zone 5B, and it does well for me.
Q. What about variegated forms of Japanese maple?
A. There are lots of them—ones with pure white variegation, or those that integrate yellow or pink into the mix.
Q. Are there other smallish maples you want to recommend, beyond the “Japanese maples”?
A. One of my favorite groups that I think is underutilized are the snake-bark maples, which includes six or seven different species. They get the name from their bark characteristic, which has prominent white striping in it—an outstanding feature on its own.
Q. Which species fit in here?
A. One is Acer pensylvanicum [photo left], our North American native moosewood. There are some Asian species, such as Acer tegmentosum, from Korea and Manchuria—it’s common name is the Manchu striped maple. Acer rufinerve, the red-vein maple, is a Japanese species. And then there is a hybrid group called Acer x conspicuum, which is kind a group with mixed parentage, including those I mentioned.
Most of these are 15-to-20-foot trees, or you often see them as large, multi-stemmed shrubs–low-branched trees. They like a little bit of shade, like in the second level under large, overstory trees—so in a woodland garden as a winter-interest element with the prominent striped bark.
In some the stems turn scarlet in the wintertime—beautiful in the snow, or against the right backdrop. There’s a hybrid snake-bark maple called ‘Phoenix’ that has incredible scarlet stem coloration in the wintertime, so you have white- and scarlet-striped stems. [Photo above: a range of features in all seasons from snake-bark maples.]
Q. Other favorite garden-sized kinds to recommend?
A. The trifoliate maples are another great group. Acer griseum, the paperbark maple [photo left] is probably the best-known, with an outstanding amber exfoliating bark, and really nice autumn color. And being a New Englander, I wouldn’t garden without sugar maple, Acer saccharum—the hallmark of the autumn in the Northeast.
Q. Give it a little more room than these other guys.
A. Yes, it’s a big tree—but there is a dwarf, called ‘Millane’s Dwarf,’ that only gets to be about 15 feet tall.
more from broken arrow
- All the maples on Broken Arrow’s mail-order site are here (even more at the nursery)
- Get details on visiting Broken Arrow in Hamden, Connecticut.
- Call Broken Arrow at (203) 288-1026 or email to info [at] brokenarrownursery [dot] com to order plants for delivery at my garden, or to get the full-color 2015 mail-order catalog.
(All photos except Acer pseudosieboldianum and top full-moon photo are from Adam Wheeler of Broken Arrow Nursery, used with permission.)
prefer the podcast?
ADAM WHEELER was my September 8, 2014 guest on the radio podcast. You can listen anywhere, anytime: Locally, in my Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) region, “A Way to Garden” airs on Robin Hood Radio on Monday at 8:30 AM Eastern, with a rerun at 8:30 Saturdays. Get it free on iTunes, the Stitcher app, or streaming from RobinHoodRadio.com or via its RSS feed. Robin Hood is the smallest NPR station in the nation.
We have two Emperor 1 in our landscape. One of them is four years old and doing wonderful. The other is brand new; just planted last week. Both face south and get full sun all day. We are in northeast Ohio (zone 5) with hard cold winters. The four yr old tree is in a protected corner. The new tree is out in the open with no protection. We thought about getting Bloodgood but were advised to get E1 instead as Bloodgood leafs out two weeks earlier than E1. The two weeks could make a difference with regard to late frosts which are common in our zone.
Any thoughts on E1 vs., Bloodgood? I’m a little worried of where we planted the new one but I love Japanese maples and couldn’t resist having another one!
Great post on my favorite tree. For the first time, I planted a Japanese maple in a container and now I’m starting to worry about a successful overwintering. We are in zone 5, middle Michigan. If I move it to an unheated detached garage, will I still need to water it and when do I take it out in the spring?
I’m at 2300 feet elevation in the Catskills, formerly zone 4 and evolving into zone 5A. Sadly, not warm enough yet for Japanese maples. In my search for Japanese maple substitutes, I planted Acer pseudosieboldianum, Acer triflorum and Sambucus ‘Black Lace’. I lost the sambucus to verticillium wilt, but both these maples are wonderful. The leaves of Acer triflorum only have that delicate look in the spring, but they are really beautiful then, and it has great fall color and decent bark.
I’m sort of in the same conditions–northwestern Catskills (Roxbury) former zone 4. I have about 15 Japanese maples growing successfully (although very slowly). I think what makes it possible is that my garden is in a ravine of a brook flowing down the southwest side of a mountain so it’s fairly protected. I can get away with a some borderline 5/6 things there (not so much on the top of the ravine, which seems still to be stuck in 4). The oldest and largest JMs are a Bloodgood, which is about 10 feet tall and a coral bark (Sang-kaku), which is about 8 feet tall. These have been there for about eight years. The main worry is a late frost, so a cold winter (like last winter) with a late leaf out is actually better. I do mulch them liberally–supposed to keep the roots cooler so they will leaf out later. (Actually, the main worry is another Hurricane Irene, which swept a chunk of the garden along with several maples away.)
I just purchased a cute dwarf acer buergerianum (trident maple) from Broken Arrow and am eager to see its fall colors
Great to hear your ideas, Brian. I think Roxbury is a little warmer than us, but you give me hope.
Thanks for the great post on Japanese maples. I am in zone 5b In Halifax, Nova Scotia and have had great luck with Japanese maples in pots including a beloved Bloodgood which is thriving in a half barrel and at least 7 years old and 5 feet tall. But far too big for root pruning so I am worried about its continued survival.I too put the potted maples in a garage for the winter successfully so far.
I would like to try a full moon maple but wonder if it is hardy enough for this treatment? They are quite pricey here and I tend to get heartbroken over losses so am seeking advice Margaret?
So interesting and so lovely! You’ve opened a whole new chapter for me to explore— thank you so much!
I too love foliage and Japanese maples. When we get our property in a more permanent landscape situation I plan to plant them. We are still changing the property layout so I’ve yet to add them in. They are so gorgeous though. I can’t wait to have some here.
I would love to adopt the potted Acers from you! The Full Moon is one of my all time favorites too
Nice to see you, Yvonne; love the potted maples, I know. Such charmers.
Please send all Japanese Maples immediately to my house. Do not pass go!! Lol
I think they are a little large for the post box… :)
SO enjoyed your lecture on birds, and your open garden day.
I loved all the trees you had in pots.
(Along with you incredible massive umbrella pine that everyone was talking about !!)
We live in New Lebanon, NY about 900 feet high. Is there a Japanese Maple that would survive in a pot – if we were to put it into the barn overwinter?
I am a similar elevation and nearly as cold as you. All mine do — whether Acer japonicum or Acer palmatum. The key is that the pots should be big to give the trees a fair amount of root insulation — so I don’t really start with tiny plants in tiny pots and put those in the barn necessarily. I have never in many, many years lost one to cold. What happens is that they outgrow the biggest pots I have and that’s a bit of an issue! ;)