Spots on Japanese Maple Leaves

ticksmom419(z7 NC)May 14, 2005

Good afternoon! I have a small japanese maple that I got as a seedling last summer. It's in a pot, sunk into a garden. The leaves came out fine this spring, but now it's developing these tan sort of bleached-out spots. Any idea what this is and what should be done about it?


Thank you for reporting this comment. Undo

Your spots look like leaf burn from too much sunlight, which could be made worse by keeping the tree in a pot. Why is it in a pot, if you've got it buried in the ground? Once a JM is established in the ground, it is much more resistant to leaf burn. However, if it gets too much sunlight and wind, it will probably always get at least some leaf burn.

    Bookmark   May 16, 2005 at 8:14AM
Thank you for reporting this comment. Undo
ticksmom419(z7 NC)

Hi, dawgie -- thanks for responding. The tree is in a pot because I don't expect to be in this house long enough to see it mature and I don't really want to leave it behind. So with the thought of taking it with me, I potted it last spring and had it on my deck. I sunk it in a garden over the winter because I thought it might need that additional insulation. It has virtually the same sun exposure that it had last year (west exposure, dappled by pines later in the day, so no more than a few hours of sun). It didn't spot last year. Are you saying that if it were actually planted in the bed, it wouldn't be as likely to burn? Is that due to greater root growth? Guess I might have to rethink my plans to keep it potted.

Thanks for your help.

    Bookmark   May 16, 2005 at 10:29AM
Thank you for reporting this comment. Undo

The spring foliage on J. maples is pretty tender and easily damaged. This looks to me a bit like sun damage amplified by water drops remaining the leaves. Not serious - pretty much just a cosmetic issue. FWIW, this can happen just as easily on young J. maples planted in the ground although older, established trees tend to grow out of it.

    Bookmark   May 16, 2005 at 11:04AM
Thank you for reporting this comment. Undo

There's no harm to growing your maple in a pot, but it does make them more susceptible to leaf spotting and drying out. You might consider repotting it in a larger container. It might just be running out of space for the roots, so it dries out quicker. It might also just be what gardengal mentioned -- spotting caused by water drops on leaves. One of my maples got leaf spotting real bad this spring, even though it's in a fairly shady location on my deck and it's a sun-tolerant variety (Emperor). I had just repotted it and moved it out of the shade too quickly. The leaves burned around the edges, but otherwise it's OK.

    Bookmark   May 16, 2005 at 11:22AM
Thank you for reporting this comment. Undo
carealot(z5 Ohio)

This looks like a disease to me. My daughbors japanese maple got it then her other tree beside it got it then my huge silver maple got it accross the street. This sucked and we put up with it for two years, finally she dug the thing up and got rid of it, this year everything is just fine so far. For some reason her tree had it bad.

    Bookmark   May 16, 2005 at 11:21PM
Thank you for reporting this comment. Undo
wqcustom(z7b NC)

Your maple has frog eye leaf spot. Caused by Phyllosticta minima. I had the same problem last year and did ALOT of research on finding out what it was and how to fix it. Bad news is this is a disease and not caused from too much sun. The good news is that this rarely does any damage to the tree, it's just ugly to look at. But since we all want beautiful trees, I had to find a way to get rid of this. The consensus everywhere I looked, was to make sure come fall you clean up all dropped leaves and dispose of them so the disease doesn't come back. Chemical treatment is rarely needed. I cleaned up my debris last fall, and so far this year, I do have it on a couple of my maples, but it is far less than last year, so I feel like I'm getting some where with it. Good luck to you!

    Bookmark   May 17, 2005 at 1:27AM
Thank you for reporting this comment. Undo
ticksmom419(z7 NC)

Thanks for the info, guys. Guess I'll keep an eye on this one. Would this small tree be benefitted by my removing the spotted leaves, in case they're fungal?


    Bookmark   May 20, 2005 at 3:33PM
Thank you for reporting this comment. Undo
wqcustom(z7b NC)

If it's just a few leaves, I would cut them off, but if it's alot, I wouldn't defoliate the whole tree. You can defoliate a tree completely in the summer, believe it or not, and get a whole new flush of growth by the end of the season. This is often done in bonsai, but cannot be done back to back seasons. I have a very young Hogyoku that had the leaf spot on every leaf this time last year. I defoliated it in August, and the tree has responded great. Here are some pics of the transformation in just one year. The tree has really taken off this year and if you look closely at todays pic, I only have about 5 leaves with the spot as opposed to the entire tree last year. I'm going to cut these off shortly.

Hogyoku April 2004 -- Was covered in spots a month later

Hogyoku Oct 5th after complete defoliation in August

Hogyoku May 2005

    Bookmark   May 21, 2005 at 1:18AM
Thank you for reporting this comment. Undo

This is likely a leaf spot disease that affects maples in spring from overwintering pathogens. It's best treated preventatively with a fungicide right after the tree leafs out in spring. It's hard to control once it starts but it is rare for it to seriously affect the health of the tree, just the aesthetics.

Leaf burn from water spots is not the cause. This does not happen and is garden myth.

    Bookmark   April 18, 2012 at 12:46PM
Sign Up to comment
More Discussions
Refreshing dirt in potted trees
Hi guys - I have 2 Japanese Maples in wine barrels....
Over-wintering small Maples on a window sill
Het, Just wondering. Can you over-winter small maple...
Timothy Wood
Need help with struggling Jap Maple
CHeck out these pictures my Japanese maple isn't doing...
Need help identifying a mislabeled JM
This Japanese Maple I bought was labeled Aconitifolium....
Japanese cultivars requiring the least sun (Zone 5)
Japanese Maple Cultivars Requiring The Least Amount...
Sponsored Products
Private Eye Desk Lamp in Black
$119.99 | Dot & Bo
FreeJack LED 4 Inch Square Flush Wood Canopy
Ivy with White Wash Planter Silk Plant
Old Havana Wall Fan by Fanimation Fans
$1,356.00 | Lumens
Chooty and Co. Shimmer Gold Round Hemmed Tree Skirt - TS512164
$52.99 | Hayneedle
Indoor Ceiling Fans: Hampton Bay Maris 44 in. Indoor White Ceiling Fan 26628
$69.97 | Home Depot
Flood Lights. 360 Degree Motion Activated Floodlight Control with Solar Stake
$59.97 | Home Depot
Romano 5-foot Indoor/ Outdoor Boxwood Spiral Topiary Tree
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™