Hotbed was originally a gardener's term for
a glass-covered bed of soil heated by decaying manure in which seedlings
are raised early in the spring. Since the eighteenth century hotbed has
been used
to mean a place favoring rapid growth of something disliked or unwanted.
At that time one writer called the theater "the devil's hotbed." Today
the word hotbed is frequently used in a derogatory manner as in "a hotbed
of sin or crime".
Another gardening term "hothouse,"
means an artificially heated
greenhouse for the cultivation of tender plants. It also does double duty
with negative overtones, meaning "overprotected, artificial or unnaturally
delicate," as in "He grew up in a hothouse environment."