Frost is the solid deposition of water vapor from humid air. It is formed when the temperature of a solid surface is below the freezing point of water and also below the frost point. The size of frost crystals varies depending on the time they have been building up and the amount of water vapour available. Frost crystals are translucent, but scatter light in many directions, so that a coating of frost appears white. There are many types of frost, such as radiation and window frost. Frost may damage crops or reduce future crop yields, hence farmers may take measures to prevent it forming.
The rose hip, also known as rose haw or rose hep, is the fruit of the rose plant, that typically is red-to-orange, but ranges from dark purple to black in some species. Rose hips begin to form after successful pollination of flowers in spring or early summer, and ripen in late summer through autumn.