Solving a simple if..then statement

I have quite a long program which is running, but I am trying to add one seemingly trivial section. I am not getting the right results, and I think it is something to do with the way in which I am setting up my if...then statement. I am novel to VBA, so I'm probably missing something simple. I'll post the code here.

For lRow = 2 To wsApt.Cells(Rows.Count, 1).End(xlUp).Row Step 1
    sMoveIn = wsData.Cells(lRow, 13).Value
    On Error Resume Next
    If sMoveIn <> "" Then
        wsApt.Cells(lRow, 5).Value = sRBeginDate
        wsApt.Cells(lRow, 7).Value = sREndDate
        Else
        If sMoveIn > sRBeginDate Then
        wsApt.Cells(lRow, 5).Value = sMoveIn
        End If
    End If
Next lRow

sMoveIn and sRBeginDate are dates, but they are dim'ed as strings. Is that a problem? Is there a way to declare a variable as a date?