Over-watering saxifrage

Does anyone have any good rules of thumb for saxifrage, particularly re watering? The climate where I live is perfect for saxifrage, and mine always get plenty of rainwater in typical years, but this April has been unusually dry and sunny so I've watered on average twice daily - morning and night. I've noticed how one or two clumps have diminished a bit so am wondering if perhaps I've over-done it?

 

Many of the Saxifrages are considered to be rock garden plants Simon, so they need very little or no water, preferring a dry site.

 

Well, not that good on alpines, but as Sheal says, once established I dont think I would be doing much watering.
I think most like sharp drainage, but probably cool and sunny conditions, not always easy to replicate.
I think once a week in very dry spells rather than twice a day.