If your temp info is correct many Jm's will grow in your area ...soil wise you can always "fix" that if necessary but mine is alkaline also...and all of mine have done fine... I think you are probably right about dissectums burning but only if in full sun all day...and any Jm' can get burnt if the sun is hot enough and they are full sun all day. Now to size...well don't believe what you read yes some can get 20-40 feet but probably not in your area ... in parts of japan oregon washington parts of CA and maybe VA and NC ...but I highly doubt it in CO....in addition that growth is over many years.... If you check out this site ( it's wholesale only ) it gives approx 10 year growth http://www.stanleyandsons.com/productList.cfm?product=Acer%20palm&fullproductname=Acer%20palmatum cut and paste it on your browser.
Now if you go to the thread on here on the GW "survived last winter zone 5" you can get from my post a bunch of stuff most of which is SUPPOSE to be for zone 5 take that of course with a grain of salt... of these I love the Beni otaki ...it seems VERY vigerous and is the right size for you and mine has done great in full sun all day ...but there are others listed by me and other folks that would work fine IMHO David

David,

Thanks so much for your reply. What a beautiful photo of Beni otaki on the Stanley and Sons Website. How tall is yours (and how old)?

I did see your earlier post about plants that survived in zone 5, which gave me hope, but then I thought, well, it's probably not as dry and sunny in Illinois (our sun at altitude 5300 ft. is intense). So I thought I'd ask, in case some are known to take sun and heat (and cold!) better than others.

I have a nice little protected spot for it, but it's protected from wind, not sun.

Will peruse your list again and see what I can find for a reasonable price.

Thanks!

Christina

You might try Acer japonicum Green Cascade. A. japonicum varieties, in general, are supposed to be more cold hardy than A. palmatum varieties. Another nice variety is A. j. Acontifolium, but it might grow too tall for your location. Green Cascade should be about the right size. Here's a link with more info:

http://www.worldplants.com/greencascade.htm

Thanks, Dawgie, I'll check those out.

The other thing I forgot to mention is that we are susceptible to late frosts, so trees that leaf out later, rather than sooner, are good.

Christina

Christina HUMMM I posted this or a facimily last night ...it's disappeared..oh well ... Yes sun may be a problem at that altitude so try to get those JM's with thicker leaves they burn less and green varieties are less prone... You can go to dave's garden http://davesgarden.com/forums/f/japmap/all/ and go to plant files at top then to the box on left hit arrow and get japanese maples ...they are in alphabetical order ...and most have planting conditions... cross referance that with varias web sites of sellers on sun exposure ...and then you'll be totally confused ;>) NO just use the info that the majority have as "probable fact". Another of mine that was in full sun and did not burn was shojo nomura ( I REALLY LIKE THIS JM ) although it budded a bit earlier (only by days though prob not a big deal and it seems so vigorous a mild frost would probably be seen as a challenge by it :>0 ) and emporer 1 which is a late budder ...but both may be a bit big although in your and my areas we may not live to see them outgrow their placements ... BTW if my earlier post appears magically hope any duplication will be overlooked!! David

You might benefit from taking a look at the PlantAsia section of the Denver Botanic Gardens, and how they have their maples sited. They don't have a large collection of A. palmatum but a few might give you some ideas. I recall them being in partial if not greater shade.

You might also be interested in seeing some other small maples of Asian origin growing in the same area. Their A. shirasawanum 'aureum' is very nice and is just leafing out now.

When I posted before, I forgot one thing about the DBG. They also have a formal Japanese Garden in the NW corner that probably has some other JMs, but I didn't go to that area when I last visited.

Inside the main administration building, directly across from the inner entrance to the gift shop, is a small room that has a computer terminal or two. You can enter the name of any species of plant and it will show you where any or all of them are located; you can mark that on the map they give you when you enter the gardens (take a pencil!).

David, Thanks so much for your ideas. I really appreciate it, since you live in zone 5 and grow these things!

I'm thinking I might get one maple for a pot and plant one in the ground. Really haven't decided yet. My soil is alkaline, which seems that it could be a problem for planting in the ground.

You plant some of yours in pots, right, and put them in a shed or garage for winter? I have a windowless shed that I could use for that purpose. Or are windows necessary? How do you know when to bring them out in the spring? Do they ever die in there--go in healthy and come out dead? Do you wait till the leaves fall off to put them in the shed?

What kind of potting soil do you use for your JMs?

Cacau, great suggestion to try the DBG. I somehow didn't remember them having JMs, probably because I wasn't into them at the time and didn't notice. I'll have to pay a visit soon. And I didn't know about the computers where you could look up plants--that's great.

What a beautiful tree A. shirasawanum 'aureum' is. I found a lovely photo of one. I'll put the link below. It seems that these get quite big, though. How big is the one at DBG? Some sources say hardy to zone 6, but if one's growing at the DBG, then they must be hardy here! Almost all the JM sources seem to contradict one another on zones.

Thanks again for the help.

Christina

Here is a link that might be useful: Gorgeous A. shirasawanum 'aureum'

Christina ...all of mine are in the ground and my experience with container growing is limited but since i've started grafting i am slowly learning ... you need to over winter in a unheated garage away from windows or bury the pot in the ground and heavily mulch ...water maybe once a month or as needed but frugilly...bring out when weather warms but be preopared to put back inside when necessary..as far as soil there has been extensive material posted here by some experts but if you are not a do it yourselfer you can buy pro mix at home depot and mix in some fine chopped pine bark...be frugile with fertilizer there is also stuff on that here too ...most maples like rose fertilizer if you arn't into the exact science as some here are ;>) I think one application in spring is all you need ...don't overdo it..Others with more experience feel free to chime in...I have tried to give a "non expert" post on basic container stuff since most of what has been posted is NOT for the novice ...or me ..although most likely better science ;>) David

The A. shirasawanum at the Denver Bot. Gardens is about 4.5 feet high. I love that tree and would be hard pressed to pass up buying one if I saw one at a good price. I think it was planted last year or the year before. In that area (PlantAsia) they also have buergerianum, truncatum, tschonoskii, triflorum, pseudosieboldianum, and a couple of others. Oh, there are at least four griseum near there, too. When I was there last week, the triflorum caught my attention especially--the foliage seemed to be canted slightly downward all over the tree, giving a pleasant angled-droopy effect--don't know if that's usual or not. Be sure to check the formal Japanese garden for other JM's.

Back against the west wall of the DBG there are quite a few Acer glabrum growing in serious shade. It's almost native to here, but I've never seen one growing elsewhere in the city. It probably grows too big for your described application, though.

The DBG has a reputation for having an especially favorable microclimate. Besides being close to downtown, it also has good air drainage because the topography slopes off to the west and south. I noticed that they got their Magnolia grandiflora 'Edith Bogue' through the winter and I didn't, and I live only two miles from there. I really don't think it was colder at my location, but rather that they picked a better-protected spot (from the wind) for theirs. The climate here is certainly unusual and is a good debate topic. It seems like we can generally count on winter minima being 5 degrees warmer in the inner city than at the airport(s) where the official readings are taken. With favorable siting with relation to a building, etc., you might be able to get by with a couple degrees more. Cycles are another thing. Over the past 100 years, official airport readings of negative 20 or lower have occurred on average every 8.5 years. The last time it happened, however, was 15 years ago. Does this mean we're "overdue," or that something has fundamentally changed? Beats me!

Two places I've seen JM's for sale locally are Tagawa Nurseries and Paulino's Gardens. Some of the best JMs I've seen for sale, though, have been at City Floral, on 14th and Kearney. They handle very few trees, but do carry JMs for small urban gardens. None of these places are inexpensive. Tagawa (not sure about the others) usually marks their trees down by 50% sometime around mid-July, so many times you can luck out if someone didn't buy the plant you had your eye on! They guarantee, too, for a year.

Cacau... I think you make some good points although I don't know if you intended them that way ..Micro climates are interesting ..#1 there is so much variation within zone 5, even within the a and b sub uzones, or any zone, a plant that grows in one area may not make it even close by. That is why it is important to put Jm's in protected areas giving them optimin chance for surviablity..also adding protection like mulch etc or wind break protection. #2 Every zone has flukes we have had 20- 25 below weather too but it is very rare about the same rate as yours...again snow cover lessens this disaster and it is usually only one or two nights ..don't know if that would severly impact a tree or not. #3 one thing that is suspicious...that in a city that large there are SO few places selling JM's...hummm that give puase to their viability there...I am in a small town and here, other than typical stuff bloodgoods and the like, they are not found but that is more understandable...we are a two horse town ..I do remember seeing a post here from someone in denver who knew someone who had hudreds of A.P. JM's in their frontyard ...you may want to look back to late falls threads it should be there...and I think they mentioned the severe differnces in microclimates in denver ..opps it may have been salt lake city ..big differnce but you can check..the microclimate info would be the same( as far as differnt ones in the same city only miles apart and may be of interest david

Cacau, I'm definitely making a trip to the Gardens this week. You've got me intrigued. I wonder if there is someone there I might be able to speak with about their JMs? I'll have to see.

Speaking of microclimates, I seem to have a nice little one in my small backyard which is very protected from wind, which is why I think I *might* be able to grow JM there. I want to give it a try, anyway. I know there are a few people who manage growing them here (maybe I'm not one, but I won't know unless I try).

I bought a small plum at Tagawa's last fall, which is doing well. I got it at 50% off. I don't know if I want to wait till July to buy a JM, but maybe. . . . I've always liked Paulino Gardens, but you're right, they're expensive (as is City Floral). I'll probably buy online for that reason. (Although Tagawa's year guarantee is pretty enticing.)

David, I'll search the forum for more info on pot-planting and fertilizing, etc. I'm not into the science of it, either, I just want my tree(s) to do well. I know I read some advice that someone had posted about putting JMs in an unheated shed for the winter. Thought it might have been you, but guess not. Sorry about that.

Grateful for the recommendations everyone!

Christina

Hi Christina & David! Sorry, I don't know anyone on the DBG horticulture staff. You might want to stop in the Library first (or call them in advance)--the head librarian (Deb) is very helpful. There used to be a gentleman named George Brinkmann, a retired horticulturist with many years of experience in this region, who held public "office hours" in the library a couple of days a week on Tues & Thurs early in the afternoon. However, I think he had some health problems and had to give that up last year, but maybe he's returned, or else maybe they've found a replacement for him. Other than those people, you might just get lucky and run into somebody knowledgeable about maples while you're in the gardens near those plants.

I meant to mention before that my garden soil tests as very close to neutral Ph. I have heard the statement that soils here are quite alkaline, but I think that's a generalization. In addition, I personally favor making moderate amendments with peat and compost to tip things a bit more toward acidity if that's favorable for the plant. Almost any plant's roots will eventually spread into "native soil" but I'd rather the new plant be a little happier when it's first getting established, and I don't think I overdo the amendments. (I know there are other "camps" on this issue.)

Yes, I'm going to take that magnolia back to Tagawa and get a refund. I'm not sure how they can sell trees at 50% off and still give a year's guarantee, unless many people don't bother claiming their refunds; I think they do ask you to bring them the dead tree! BTW, I'm sure there are various other places that sell JMs near here, and at more attractive prices--esp. "big box" stores, but they're less likely to have the unusual we sometimes need and crave.

I'm fascinated by microclimates myself, but unfortunately I've been able to find very little written about the subject. From what I've been able to gather, there seem to be two aspects to plant hardiness. The easier one to deal with, probably, is the root zone temperature environment. I've read that damage starts to occur there at temps lower than 28 F. A good mulch layer can protect against this potential damage, and a nice layer of snow can do even better. However, cold air temperatures below some point will damage stems and branches, the point depending on the hardiness of the species. I think that's why some marginally-hardy trees are sometimes referred to as "stump-sprouts"--most of the above-ground parts of the plant die but the root system doesn't (at least for a number of years). Of course dessication is a separate problem for above-ground plant parts, especially in this sunny-winter climate.

Other than the most general principles and trial-and-error, it seems difficult to predict microclimates. There are so many factors involved besides topography. For example,the influence of a building to the north of a plant may be very different depending on the building's height, mass, color (solar absorption) and configuration. Also, if one is depending on stored solar heat being radiated at night from a building face, it will make a big difference whether the days following the initial cold wave are sunny or cloudy, still or windy. Another aspect of the problem is how far away the influence of a building is felt and how fast the influence drops off with distance. I know of a student who is investigating this question at the U. of Denver near some of the larger buildings on the campus, but I haven't heard any of the findings yet.

Christina, if you go, I'd like to hear your reaction to the various maples at the DBG!

Cacau, I haven't actually tested my soil, just always heard we're alkaline here. I suppose I ought to check and make sure.

Btw, though it's a big box store, Lowe's has decent plants sometimes and they also have a one year guarantee (was there the other day and saw a woman returning two dead bushes).

Will let you know about my DBG visit.

Christina

Well, made my trip to the DBG yesterday (May Day--seemed appropriate!). I missed a lot, though. I looked up my plants in advance and still managed to miss several of them. There are supposed to be a bunch of Acer palmatum planted in the picnic area, but I couldn't find any of these. :(
Did see several in the PlantAsia section. Their Red Emperor looks real good. They had a japonicum Green Cascade in a pot--since this is one I am considering, I was glad to find it. I somehow missed the Acontifolium-- unfortunately, because I am considering that one,too, and Cacau said it looks great.

Oh, and the Japanese Garden is under construction, and this is where several of the A. palmatum were supposed to be.

I was also looking at dwarf conifers, which they have a lot of. The problem was that unless they were right by the path, I couldn't identify them since you're not supposed to walk in the garden (climbing on the rocks and stuff would be kinda uncool, I guess).

I didn't realize it when I headed out for the Gardens, but it was a free day. Good and bad news. Every mother with a child under the age of five was there, plus anybody else who wasn't working, which made it very, very crowded. It was a beautiful day, however.

All in all, a less-successful-than-I-had hoped-for visit. One of the problems was I had too big an agenda--wanting to see a lot of dwarf conifers plus the Japanese Maples, and not enough TIME! I am going to have to go back. When the Japanese Garden is open. My husband wants to go, anyway, and he couldn't make it yesterday.

Still trying to decide on a maple. My top choices change daily and I'm wondering if I'll ever order. . .

Christina

I meant to say I missed the shirasawanum 'Aureum', not the Acontifolium (which I don't think they even have).

Christina

Sorry your visit to DBG was underwhelming, Christina. I've also at times had difficulties finding the plants. It's actually a bit easier now to see labels because there is less foliage "out" at this time of year to hide them. I know about that temptation to step off the paths to read labels and I'd be lying if I said I never did it. People often steal the plant labels, too, I've been told--they forget to bring a pen and can't trust their memory?

I'm glad you got to see some small conifers you're interested in, anyway. The A. shirasawanum--it's hard to explain where it is because the paths are winding, but I'll take a stab and say ten feet southeast of where you saw the japonicum in the big pot (which is near a little "gazebo" alcove-thing, right?). It always seems to stick out to me because the foliage is markedly yellower than the other maples (but to me it is still definitely a shade of green, nowhere near yellow).

The PlantAsia section is quite shady, isn't it? Everything is so tightly packed in there. It's one of the problems with the DBG that they don't have the space to allow as many trees to develop to maturity as a full-fledged arboretum would have. All those Asian maples that want to grow to 20 or 25 ft. tall...I wonder what they will look like in 10 or 15 years packed in like sardines there?

Cacau,

Hope I didn't sound too whiny. I was happy to get over there, just disappointed that I didn't plan it better (it turned out to be a last minute thing). I'll just have to go back! I didn't pay anything for my first trip, so that helps.

I must have been so close to the shirasawanum. Bummer! You remember correctly, the Green Cascade is in a pot in the little gazebo, so I must've been right there.

Yes, PlantAsia is very shady, which was a welcome respite after looking at all those conifers in the sun!

Btw, do you know what the whispy sort of JMs are that grow to the left of the gazebo (if you're standing facing it)? I could not find markers (maybe somebody stole them!). They look kind of "ghostly." I turned in my map at the end, so can't tell for sure which direction that is, perhaps westerly. If you don't remember them, I could try to post a photo, but never seem to be able to figure out how to do that here.

Thanks for your recommendation to visit the Gardens, it was an excellent one. I have been negligent in getting over there in recent years. I wonder when the Japanese Garden will reopen?

Christina

Hi Christina,

I don't recall the JMs to the left of the gazebo; yes, I think that would be to the west. I'll probably go again in the next few weeks and if I can ID them, I'll post a note here, as well as whether the Japanese garden has reopened.

Cacau, I'd appreciate it if you let me know if you can id those; it's not a big deal, though, I was just curious. And I'd really like to know if the Japanese Garden has reopened when you visit.

Thanks!

Christina

Hi Christina,

I visited the DBG today. I didn't take notes, so am going off memory. In the PlantAsia section there are three JMs in pots inside the gazebo. One has died, one came close but is making it back, and there is a 'Green Cascade.' Just outside the gazebo are three more. One, 'Higasayama,' was my favorite, gorgeous leaf color & form. The other two had no labels (true of many of the others, also); I don't know enough about JM cultivars to ID.

Southwest of the gazebo there is a pretty nice 'Red Emperor' under a honeylocust tree. There are eight or so others scattered around that general area. Of course the shirasawanum 'aureum' is still there going strong, but butting up from below against another Acer.

The Japanese Gardens are now half opened--the eastern section of it that includes the Teahouse. There is an 'Atropurpureum' there, but no other JMs that I saw. I didn't see any in the walled-off section, either.

I'd recommend waiting a few weeks to go back. Quite a few of the trees are still in early stages of recovering from the April freeze.

Cacau,

Guess I haven't checked this forum in a while. Been busy in the garden. :)

Thanks for the info on the Gardens. I'll take your advice and wait a bit before venturing forth again. I do remember the Red Emperor, and it was very pretty. I will have to check out the shirasawanum 'aureum' next time.

I was at Timberline Gardens yesterday to get some gravel and saw a couple of real nice Full Moons. I don't know exactly which type, as I wasn't shopping for JMs, just looking, so didn't examine the tags real close. They were very attractive and big. I don't know whether they have a guarantee like Tagawa does, or not, but if they did and I had the money (and space), I'd be tempted.

I planted my two--the Sharp's Pygmy I bought at Tagawa and the Beni Otaki I got on E-Bay. So far they seem happy. I'm keeping my fingers crossed.

Christina