No such thing as too much mulch IMO. Go ahead and put anywhere you have room. Our soil is so poor in organic materials that it can be used anywhere. It will disappear very quickly also. If you want to save some mulch to mulch around you new citrus trees, that is also a good option. Remember not to backfill with the mulch though--aztreelvr will also reiterate that. Also remember to keep it several inches away from the bark.

Good Luck and HTH

What is meant by the "remember not to backfill with the mulch'? Does that mean not to add mulch right up to the trunk of the tree?

Janet

Never mind - I think I understand. Backfill means the dirt/amended soil that you are planting the tree in.
Janet

Here's a link that's worth a read. Granted, it's from vermont but there is a lot of useful backround.

Here is a link that might be useful: Mulch