Quercus Virginiana Dropping Leaves

rockm

Where do you have the trees? If they're inside, they're not going to survive, or course if you put them outside, they won't make it through the Minnesota winter.

The problem with live oak is they aren't tropical plants, they are mostly subtropical to temperate climate. They need a little cold to stay fit, that, and ALOT of sun in the summer and even into the winter.

I have a large collected, old quercus virginiana that was dug from the Texas prarie about 10 years ago. I live in Va. near the northern end of the species natural range. I keep my tree outside all year round here. I provide winter shelter in a poly tunnel in the winter. The tree is fully winter hardy, but winter hardiness in this species can depend on its origin.

There seems to be a hardier subscpecies called quercus virginiana "fusiformis" that grows in upland habitat, like inland Texas and even the mountains of Mexico that can stand colder temperatures. The coastal variety of quercus V. can't take lower temperatures. This species grows along the Gulf coast from Florida to Texas. If your trees are from there, then they probably need to overwinter in a greenhouse where the temp is lower, but not below freezing.

Indoors, light is a big problem for any tree. Live oak is no exception. This species love sun, alot of sun, or it won't do well. Again, I'd get your plants into a greenhouse for the winter and watch the watering.

For what it's worth, live oak isn't entirely evergreen. It just retains its green leaves until spring, then drops them almost all at once in a week or so as new leaves emerge. This usually happens in mid-Feb, to mid-March, but is highly variable depending on local conditions. New growth indicates the leaves might be dropping because of this, but in any case, you've got new growth at the wrong time of year.