INHERITANCE OF THE DAY-NEUTRAL TRAIT IN STRAWBERRIES
We prefer to use the term day-neutral rather than "everbearer" because it is more descriptive of what is really happening in strawberries in relation to the literature on the subject for a great many plant species. In addition, the so-called "everbearing" strawberries may just as accurately be termed long-day type plants, given the mid-summer to fall fruiting pattern they exhibit. When they sense the short-days and cooler growing conditions of the fall, they go into a state of rest and will not grown very well until spring since they have a fairly high chilling requirement. Our day-neutrals have less of a chilling requirement and thus can be made to grow during the short-days of winter in relatively warm winter, cool, summer environment of coastal California and may fruit cyclically throughout the year there.
By the same token, we prefer to refer to the standard "June bearing" strawberries as facultative, short-day plants in agreement with much of the modern literature.
The origin of day-neutral strawberries is not entirely clear, but two explanations are likely: