"In warm-winter climates, ... fruit growers sometimes find that a variety produces well with much less chilling than “advertised”. This could be because their locations receive relatively few hours of chilling below 45°F but plenty in the 45-55°F range (perhaps lots of foggy days), or because the variety’s chilling requirement is actually less than stated.
"Researchers suggest also that some varieties in the absence of cold are better able than others to "switch" to a heat requirement for triggering bloom and setting a crop."