Why not acquire a holding tank/container of suitable volume, elevate it to
assure adequate water pressure, and pump the water into the
tank/container? Then when the tank/container is full or nearly so, turn
off pump. Tank/container volume should be such as to support minimally one
watering cycle.

I thought of that, but not sure it's worth the trouble and expense. I'd have
to basically put it on the roof to get the pressure I need, or build a tower
or something. When I lived in Saudi Arabia, we had a flat roof with a water
tank on the roof. We had to manually turn the pump on and off to fill the
tank. In the summer, the water tended to be luke warm because it was hot and
the tank was in the sun. That is the kind of tank I need!