The top of the dirt looks dry but they have better soil underneath that retains moisture better (I even check an inch down occasionally and it is still wet). Our dirt does not drain very well and acts almost like a barrier underneath so the roots stay wet for several days.
Did they have a fountain or pond in the courtyard? We have an above ground pool and are one of the few neighbors with fireflies in our yard. We also have a lot of native flowers though so maybe that helps