I have three maples in large containers (>24) on my south facing patio. Every fall the leaves seem to turn brown and crispy (from the edges inward) before they have a chance to change to show off their potential for beautiful autumn colour. Why is this? They are kept well watered, with excellent drainage, aprox 6 hours sun/day and sheltered from wind. This has been a mystery that has nagged me for three years now; being the eternal optimist I had hoped they would acclimate - assuming the problem was environmental. Any ideas? Sincerely, Judy
It would be nice to see what the leaves look like but I suspect you have a salt problem of some sort. Salt buildup in a container plant will show up in the leaves. We will see a browning of the leaf edges that makes a concentric ring of browning inward towards the center of the leaf. It is not unusual here to see leaves that are crispy on most of the leaf yet the interior looks to be okay. In Fall these leaves will have the centers quickly turn the beginnings of Fall color and the whole leaf just shuts down within a couple of days. This can be worse on red leafed plants more so than on green leafed Maples. There could also be a problem with your soil medium that can cause a faux salt symptoms in that the leaves will tell us salt buildup but the soil is still somewhat acid. Look at the top of the soil layer or in the interior sides of the container and tell me if there is any white to brown crusting, a precipitate showing? Have you been fertilizing these trees and if so, what fertilizer are you using, how much of it and how often do you apply it? Whether you have a salt buildup or not I think you may need to change your soil. If the trees are protected from intense sun and winds, get ample amounts of water and you do not have drainage problems, then you may want to think about lifting the plants out of their containers, lightly knock off the old soil and give these trees a new soil medium to work with. How old is the soil and what soil and/or potting soil did you use? Jim
