There is a morning in May, usually along Pinebrook Boulevard, when the heads come up for the first time and the whole lawn is briefly full of small rainbows. Eden's Garden Sprinkler Systems lives for that start-up week — charging the lines, walking every zone, adjusting arcs so the water lands on grass instead of pavement. New Rochelle summers turn dry in stretches and then dump two inches in an afternoon, so a system here has to be tuned to the yard's own slope and shade rather than left to run blind. Set it right and the difference shows all season in even color from the street to the back fence. In autumn the work runs the other way: the lines drained and blown out before the first hard freeze, so nothing splits under the frost.