I really struggle with Japanese Maples and I don't really know why. I've had two major ones that I've been growing out, but killed one last summer because I forgot to water it
My second maple has been going for three years now, but not without its problems. It's branches are heavily sunburnt and its leaves are starting to yellow for some reason. It currently sits in a shadehouse and gets sun pretty much all day. I think this has been a major mistake. I've just moved it to a position under an awning, where it will get morning sunlight and that's it. How does this sound?
But yeah, how better can I look after my Japanese Maples?
Japanese Maples are such a pain. I'm in Melbourne most of my Maples are in dappled shade all day. I have a few that are in morning sun only. I have others in large pots not bonsai, in full sun around the garden the leaves get scorched every summer but they regrow so no harm seems to be done to them. I have found Maples as bonsai hate drying out and hate having wet feet so you have to keep ontop of their watering and have a very good draining mix. Even with being careful I have lost trees to fungus so like I said Japanese Maples are such a pain I seriously wonder why I bother with them.
Cheers
Kirky
There are far more knowledgeable people here and happy to be corrected. My understanding is morning sun = good, afternoon sun = not so good but more importantly very hot, dry wind is bad.
Some of the ones in smaller pots get shade cloth this time of year . I have a larger one in a styro box exposed full sun year round and it hasnet burnt to date . Remember different forms will be more effected to the elements then some . Hot wind is more dangerous then direct sun in my opinion .
Guys,
I have three(3) Japanese Maples and a number of Tridents plus one "compestre" and if I neglect the watering discipline in hot weather then yes I have seen a few scorched leaves but as a general rule I find all three very weather tolerant.
One(1) of my Japanese Maples is in a "grow" garden(about 8 years old) and receives direct sunlight about 3/4 of the day then shade, one is a Shohin in a container(about 5 years old I believe) and receives direct sunlight 1/2 the day and then shade and one is quite big in a container(I know this one is 20 years old) at 70 tall x 80 wide and gets direct sunlight all day every day(the "compestre" is all day sunlight and tridents vary).
It may be a case of "get used to it boys" particularly the big one because I know from its previous owner it never moved out of direct sunlight all its life but similarly I don't move any of them I just turn them every week for a week.
I have a good friend at CBS who is also my golfing partner who has some 40+ years experience at this and has many Japanese Maples and I believe his never move, other than being turned regularly, are to varying degrees in direct sunlight all day and I can assure you they are all gorgeous.
Now one small fact that may be of importance and that is we live in Canberra so it could be said(just putting it out there) that not much shines in Canberra anyway so we have it made but I don't find them a pain and it's a shame you are having issues because they are quite beautiful.
There are many very experienced people on this site who I feel sure will post on this issue and may well solve the problem.
I came to the conclusion a long time ago that I wasn't going to have a Japanese Maple that looked as good as the ones in the magazines, and that they'd look great in winter and early spring until we got the first hot northerly and then the leaves would get a little crispy around the edges. Good autumn colour is pretty elusive too on the Adelaide plains. It's just too dry and the autumn/winter temps too high.
Having said that if I keep them in dappled light through summer and there's a bowl of fresh water nearby to keep the humidity up, and keep up a few partial defoliations then they can still look fresh through summer. Why do I bother? Because they're beautiful in winter and spring (and like everyone else I read an article from the northern hemisphere and get inspired to try it myself!).
All my Japanese maples are currently in full sun for most of the day. When it gets properly hot I will put up 30% shadecloth and the JM will be amongst the trees that will be under the shade.
There are probably a number of factors influencing whether or not maple leaves burn. Some have already been put forward.
Water - this is not as simple as it sounds at first. Different pots and different potting mixes have differing water holding capacity so even very effective watering technique may not be able to put enough water into some pots/mixes.
Watering technique is very important. From autopsies on dead trees I know that some have not been getting the required water despite me watering twice each day - mix in the centre of the rootball was dusty dry while edges were wet. Lots of things influence how effective watering is- pot bound trees have so many roots that there is no physical room for water in the mix so no matter how well you water the tree won't get enough to last the day. Recently repotted trees definitely do better here.
Initial water onto dry mix nearly all runs off and is ineffective. A second watering soon after soaks in much better and a 3rd may get to the centre of the pot. Occasional soaking of the entire pot can help rehydrate dry pots.
Hot winds - I suspect that JM are just not able to pump enough water to keep the leaves cool in really hot areas, no matter how much water they have available.
Shallow pots- I've moved toward deeper pots being more appropriate for our hotter and drier climate. Trees seem to be doing far better in deeper pots.
I suspect we may find that the same techniques may not be appropriate for different areas and that people will need to trial different shade/water/mix combinations to get a useful balance.
It is also possible that Toowoomba location is not altogether conducive to Japanese Maples. Remember they are adapted to mountain areas with quite cool climate and large daylight differences. When grown in other areas some of this may add some stress to the tree metabolism.
I'm in suburban Melbourne where we tend to get quite hot and dry summers (not ideal for JM)
Mine are in full sun or at least half day sun at the moment without any ill effects. Having said that the garden is protected from hot winds which JM tend to hate. From my experience with many varieties the straight species are quite tolerant up to about 35 degrees with protection in the hottest part of the day and obviously adequate watering.
I will move them around to a morning sun/ afternoon shade position as the weather starts to heat up further in to summer and once it passes 35 or so i actually move sensitive varieties indoors into the garage for the hottest part of the day then back out in the late afternoon/early evening. It's a pain in the ass but i don't see much point leaving my trees out in 40+ degrees to get stressed and burn all their leaves off.
I concur with deeper pots for JM, after moving a sickly one out of a ridiculously shallow pot it originally came in that wouldn't have even been an inch deep for a size able tree, into an unnecessarily deep pot. Granted it looked great in a very shallow pot but it was certainly not doing it any favours. The main help for the tree was removing some seriously shitty old soil that was waterlogged and preventing oxygen penetration to the roots, but i'm certain it also appreciates the extra space to spread it's roots out into and has grown on well this season so far. It's certainly not 100% health wise yet and i'll need to fully bare root it next year to clear the last of the shari soil off, but for now it's a huge improvement.
All my Japanese Maple leaves fry/burn in the hot summer sun in Melbourne.
To protect against this, my bonsai and any seedlings are in morning sun (until around 11.30 AM) at this time of the year and the dappled light of a large Chinese Elm in the afternoon. Good airflow in the courtyard but protected from any fierce direct winds. I will water at least once a day - sometimes twice. It is a reasonably free draining mix - but not as loose as mix I'd use for say pines. I reckon they like to be moist but not wet if that makes any sense. I use shallow pots but cheat because I mound the soil quite aggressively to create landscape effects ... so, deeper pots make sense - albeit I guess - there is more surface area on my soil - I am not sure how that might affect positive growth habits or not? Also, my JM's - seedlings or other - seem to thrive on mounds in shallow pots and under moss ... so ....perhaps they like their surface roots cool?
In my experience, hot wind and/or hot direct sun are the enemy of my Japanese Maples but I suspect there is an element of acclimatisation too. Still humid conditions are also not great - in the past I grew them in different area - protected, reduced airflow and more humid. There seemed to get various diseases in these conditions.
In early spring and late autumn - no drama with full sun in my experience; essentially I am wary of anything over say 30 degrees with my JM's
All this is just my experience, I am not expert, I wish I was.
Hope this helps.
Cheers,
Mark
PS - I get worried when I see experienced growers having problems with Japanese Maples - I wonder whether my success (to date and touch wood) is more that mine are young and it is much harder to keep older trees alive perhaps? As a side note - with my JM's I never fully defoliate, rather partially defoliate 3-4 times across the growing season as leaves harden off. I am also mindful of die back - so I always leave a stem and allow it to die back and clean up later.
