Question
My tibouchina tree has holes in the leaves and has white insects with hard crusts!  Ehat are they and how can I kill the.  One brown (large) flew away! I have used Malathion and still have the problem.  Also leaves turn yellow and thenn brown and fall off the tree. Also, can I cut the tree back after it blooms?

Answer
Hi George ...Holes in the leaves are usually from snails or slugs on the inside of the leaves and grasshoppers on the outside eating in.  An insecticidal spray like Neem would help correct that.  Spraying on the ground as insects don't like walking on it. Sounds like scale which will also help keep them off.  Even if your malathion worked the scale would remain, you would have to push them off.  If you press into them and they are alive they look like blood come out.  It they are dead they just crumple.

The yellow leaves could be just from transplant.     I do not know know which one you have but I have noticed mine do better in morning sun and afternoon shade.  But that is in pots.  It is too cold to grow in the ground here.  Spray your leaves also with the spray, just in case or for future protection.  I don't think you picked a bad plant just one that is a little tricky in the beginning.  If your soil is sandy you may have to water a little more than if it had a lot of clay in it.  As good drainage is of utmost importance