Varieties of our fruits differ materially in their blossoming habits. Some varieties expand all their flowers in a brief period. Others seem to have two sets of flowers. As an extreme example, some of the east European cherries when white with blossoms show many buds still unopened. If the first bloom is destroyed by frost the later ones are numerous enough for a full crop. If both mature fruit we have an early and late picking. Close observation will show that many of our fruits that do not ripen the crop evenly have a long period of blossoming.