The chilling requirement of a fruit is the minimum period of cold weather after which a fruit-bearing tree will blossom. It is often expressed in chill hours, which can be calculated in different ways, all of which essentially involve adding up the total amount of time in a winter spent at certain temperatures.
Some bulbs have chilling requirements to bloom, and some seeds have chilling requirements to sprout.
Biologically, the chilling requirement is a way of ensuring that vernalization occurs.
Read more about Chilling Requirement: Chilling Units or Chilling Hours, Chilling Requirements, Models, Stone (prunus) Fruit Tree Selection Guidelines To Match Local Weather Conditions
Famous quotes containing the words chilling and/or requirement:
“I swear to keep the dead upon my mind,/Disdain for all time to be overglad./Among spring flowers, under summer trees./By chilling autumn waters, in the frosts/Of supercilious winter—all my days/I’ll have as mentors those reproving ghosts.”
—Gwendolyn Brooks (b. 1917)
“Reporters for tabloid newspapers beat a path to the park entrance each summer when the national convention of nudists is held, but the cult’s requirement that visitors disrobe is an obstacle to complete coverage of nudist news. Local residents interested in the nudist movement but as yet unwilling to affiliate make observations from rowboats in Great Egg Harbor River.”
—For the State of New Jersey, U.S. public relief program (1935-1943)