I purchased a Japanese Maple about two years ago and repotted this past spring into a wooden box to try and get a larger trunk. Everything seemed fine after repotting and the leaves came out nice and green. I’ve noticed over the course of the summer that they have lightened up significantly and wasn’t sure if that is normal for this tree.
I unfortunately do not know the variety of Japanese Maple this is. I was told in the winter when I bought it that it was a red leaf JM and something tells me that isn’t true .
Fall is approaching, so the tree is entering its next phase, leaf drop.
On another note, if you would like a thicker truck you will need to put it in the ground and let it grow. No pruning, except for structurally flawed and dead branching. Fertilize heavily
it looks like a variegated cultivar, a friend of mine has an arakawa that does this, it could also be a seedling. I usually don’t buy a tree if it doesn’t have any identification. Go to your local library and pick up JD Vertrees Japanese Maples, I think I saw your tree in there.
Your ID tag doesnt say, and you dont mention where you are…
Whats your local water pH? High? Call your water supplier and ask…
That would add to the magnesium / iron comments problem above…
I would agree with Marty W. this looks like typical chlorosis. Not enough iron or other ions available to support chlorophyl production. Typical pH of water should be closer to 6.5, which makes these ions more available. You might try acidifying some of your watering with 1tsp to 1Tbsp vinegar per gallon of water. If you use soluble fertilizer acidify your fertilizing solution with the same ratio.
You may have to grow new leaves to see the change. At this time of year there may not be new growth.
Another thought, I you have had this for two years, what were the color of leaves in the past summers and falls? Maybe your soil mix is different than what it was growing in before?
MM
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