My eucalyptus tree still has last year's brown leaves on it and I see no new growth. This is a mature tree, probably 30 feet tall. We have owned it for two years in our yard. I am not sure if anything is wrong or not. It is just that everything else has leafed out and is in full-on spring mode, and this tree looks like it did all winter. The leaves turned brown/dark green but did not drop last fall.
Eucalyptus Tree Not Leafing Out
Certified GKH Gardening Expert
If your tree did not shed it's leafs in the fall, chances are then that it may have been in trouble prior to winter.
Did your tree receive adequate water?
Do the branches snap off when bent?
Do they bend? Then there may still be life in the tree.
Are there any other signs of disease or damage to the tree?
A wait and see approach is recommended at this point.
Here are a few links with information about care and possible problems with eucalyptus trees.