Does sound like a moisture-related problem, check original rootball. Here is a link that might be useful: Horticultural Techniques For Successful Plant Establishment

Leaves also fall off trees this time of the year, and oldest ones go first. Norma

Yellowing leaves is perfectly normal this time of year. It's not from cold so much as part of the normal senescence of leaves with resorption of the material in older leaves. It is normal. Wait a little while and they will fall off on their own, or just pluck them or bump them. They should be very easy to knock off the stem. It is just the plant getting ready for new growth. No worries. Brad

I am just trying to figure out why my jade succulent is yellowing and losing its leaves from the bottom up. It is not from overwatering, I only water once the soil is dry. The plant gets full to partial sunlight, the leaves are a little red so it might be getting a little too much sun. Could It be a nutrition problem? Does the plant need to be repotted? It's has been in that pot for a while.