The season
of the year between Autumn and
Spring
when plants
stop to vegetate. Most plants go through a
dormancyphase this time of year.
It begins with the
the winter solstice
(around
December 21
in the Northern Hemisphere,
and
June 21
in the Southern Hemisphere),
and ends with the vernal equinox
(around
March 21 in the Northern hemisphere and September 21 in the
Southern hemisphere)
It runs from December to february in the Northern Hemisphere,
and from June to August in the Southern Hemisphere.
Winter is the
season
of the year in which the sun
shines most obliquely upon any region and days become shorter (
See: Photoperiod), The
coldest season when temperatures
drop and snow
(if any) begins to fall. Plants undergo
physiological changes
that will allow them to withstand
freezing temperatures. (see:
Winter rest,
Cold
resistance).
In normally snowless
areas, a short and mild "winter" may begin as lately as January.
In subtropical
zones the differences are very subtle, and in tropical
ones none at all. In the subarctic
areas winter start early in October or even September, or in May
in the subantarctic
