Japanese Maple dying out ?

Hi,

I currently own two japanese maples, a red one and a green one, bought around 2.5 months ago. They are currently exposed north-west. I also live in the middle of France. There's often wind so I put them behind a wall.

The state of the red one is currently worrying me. It all started with leaves sort of burning (getting grey or dried out). I started watering it a bit more, since it seemed to be either sunburn or because I wasn't giving them enough water. It seemed to alleviate the issue.

However, recently, I noticed a lot of white spots appearing on the trunk (mostly on it, branches have little to none so far). You can see in the back that the green one is starting to get a few as well.

I don't know what it is and I'm afraid I'm doing something wrong. Can you give me some advice to save them ?

Here's a few pictures :

Sun damage or something else ? The red one is the more exposed to the sun. How can I avoid that given my exposure ?


The white spots on the trunck.

Thanks in advance

 

Hello from Normandie. It's very difficult to diagnose problems from photographs, but from the trunk I can tell you: the "white spots" are normal, that's just a typical marking that the trunk gets. And, the leaves look like the soil may be too wet, which again I see in the second picture the soil seems very fine-grained. You usually want something with more drainage and a rougher texture.

 

Hi,

First, thank you for your answer.

If the white spots are normal, then there's one less issue.

As for the soil I'm using, it is heather earth (I'm not sure on the translation, the French name is "terre de bruyère") as indicated by the seller. I did add drainage to the bottom of the pot, but my guess is that their wasn't enough.
Since it's almost June, do you think I can safely repot the maples now ?

 

Your welcome, no problem. So, firstly terre de bruyère is not ideal for maples for many reasons, although it is a standard French myth to recommend it. (Many sellers are not maple specialists, so their advice is not always good). Japanese maples don't mind the acidity of such soils but don't require it either. And of course there's a difference between the artificially acidified version and the peaty version, but they both have the same problem: drainage. They hold too much water and you will have a very hard time getting a happy maple in that medium.

After the maple is done with its first flush of growth, which is to say around now, is an excellent time to repot. I try and pot up to larger sizes in June in possible, it gives the maples time to put on root and let new growth harden off before winter.

You need to mix grit, like pouzolaine, perlite, small bark chips etc in with the existing soil at about 50% ratio. That will give you the fast drainage you need. Use less if you are in the South where it gets very hot and you need a little more water retention. Do not add extra "drainage" to the bottom of the pot, that only serves to raise the water table in the pot and will cause even more problems. Make sure you only water when the soil has pretty much dried out; maples hate over watering.

Stop fertilizing if you have been doing so, until next year with a teaspoon of osmocote. Ensure you don't plant deeper than the root flare of the maple, I can't quite tell but perhaps this is planted too deep.

After repotting make sure the plant is in a partially shaded area for 4-6 weeks.

-E

 

Are they in the same container?

Anyway, you cans always slip-pot them (les "transpoter") without meddling too much with the roots, and add some free-draining mix. Small gauge pozzolane is now available in some garden centres (about 5 mm), you can mix some with regular planting soil (terreau de plantation), it's acidic enough if your water is not too hard. Whereabout in "Centre" do you live ?

PS: when I saw you were from France, I replied straight away without reading Emery's answer, which is the best one you could get ;-)

 

Both are indeed in the same container. I may need to buy a slightly higher one since they are planted just at the root flare (a few small roots are at the surface).

To be more precise, I live in Bourges (so just in the middle of France).

 

Is this "heather earth" manufactured potting mix using "recycled forest products", AKA newspaper? Those crispy edges are indicative of too wet and/or over-fertilizing.

 

I think you should put them in seperate containers for several reasons. First, perhaps they have different requirements, one will fare better in full sun, while the other will require some shade, or one will dry out faster, etc. And if one gets sick, it will be less likely to contaminate the other.

If you want to keep them together, two square plastic pots can be placed next to each other. You can find some that are quite cheap and perfect for that purpose.

Concerning "terre de bruyère", whether it's "real", natural product or the "manufactured one", from what I heard it is advised that you mix it with some soil (terre de jardin), even for azaleas.

Nice city Bourges, beautiful cathedral. Last time I went there was years ago though, for the music festival...

 

Just root pruned and re potted this dissectum on Monday struggled through out the spring and it wasn't looking to clever, so when i took it out of it's previous pot i was amazed at the growth of roots which were present not supprised it wasn't growing and pushing out good leaf , only did this one two years ago came out of the ground and into a 25ltr pot just put it back into a 45ltr big move up but it certainly needed it.

Find this happens alot especially with new trees which i sometimes buy in every year , they proably have been in their present pots for xx number of years then i get them and after the fall give them a good root prune and fresh growing medium plus a bigger pot and they just explode the coming year with exceptional growth rates , this one seems to have taken it's new growth to fast and the pot was girdled all the way round, had to take quite a large chunk of the roots out to bring it back to how i usually like to see them when i re pot.

Hopefully i just caught this one at the right time, the good leaves that were present look ok but it's still early days, will see come the second flush if we caught it in time :) all the branches are fine no die back look in good condition, just wait to see some new back budding.