Answer: Zoysia is actually a low-input lawn grass. Typically it needs only an application of about a pound of nitrogen per 1000 square feet in the spring when it is turning green. It should crowd out weeds on its own so you would not need to routinely apply herbicide. If you have a specific weed problem, you might want to consult with your extension service to identify the weed and then as to how they recommend treating it. Here is the contact information for them.
Their web site also includes lawn care information you may find interesting, there is a sheet specifically for zoysia.
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