Question
Thanks for the reply Will. The leaves are actually rotting off where they attach to the stem.  It is an actual rot and not just the leaf falling off.  The stem of the leaf is actually a little "mushy" and black.  
I repotted it into the same pot but decided because it had been in this pot for 3 years it needed some new soil.  I dumped it out, cleaned up the root ball and repotted it. It did very well after that and I got lots of new growth.  I still have plenty of new growth, but at the same time it has this leaf drop.  I've checked for pests, my watering habits haven't changed and I haven't moved the plant.  I can't find anything that describes my problem.  Thanks in advance
Alyce

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Followup To
Question -
I have a scheffelera that has recently started dropping leaves.  They appear to have rotted off at the stem.  It has been in the same pot for three years and doing just fine.  I did "re-pot" about 4 months ago simply to add new medium, and check that it was not root bound. I have not changed my watering or fertilizer habits, it remains in the same location and there is plenty of new growth.  What could be the cause of the leaves rotting off?
Answer -
Hi Alyce,

I am not clear about what you are describing. Is it the main stems that grow up out of the soil that are rotting. Or are they rotting where the leaves attach to the stems. Are they actually rotting or are they just falling off?

If you can e-mail  a photo to me at my address below, that would help.

When you "repotted," did you move it into a larger pot? If not, where did you add the new medium?

Regards,
Will Creed

[email protected]

Answer
Hi Alyce,

The symptoms, timing and sequence suggest that the problem started with the repotting.

Replacing soil is never a good idea. At a minimum it disturbs the roots and stresses the plant. It is quite possible that the older lower leaves are reacting to the stress of the soil replacement. The healthy new growth suggests that. If so, the leaf loss should gradually diminish and stop. If it does not, then you may have a larger problem, described below.

It is possible that a pathogen or disease was introduced with the new soil that you added. The process of removing old soil inevitably damages some of the roots and renders them very vulnerable to bacterial and fungal infections. Without a lab anaysis, there is no way to tell just what pathogen may have infected your plant and therefore how it should be treated.

Finally, the roots may be staying too moist as a result of the soil replacement. The new soil may retain more moisture than the old and the roots may be using less moisture as they try to recover. If you are still watering the same as before, the roots may be rotting. Make sure the top quarter of the soil is drying out in between waterings.

Have I persuaded you that soil replacing is not a good idea?

Please let me know if any of this is unclear or if you have any additional questions.

Regards,
Will Creed, Interior Landscaper
Horticultural Help, NYC

You can E-mail me directly at: [email protected]

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