Mojave River Valley Museum
The vegetation of the Mojave and Colorado deserts:
An annual plant germinates, grows, flowers, sets seed, and
dies in less than one year, avoiding drought in a dormant
state within the seed. Annuals are also referred to as
“ephemerals” due to their short lifespans. Seeds of desert
plants remain viable for long periods, only germinating
when conditions are right. Winter ephemerals germinate
and grow in response to sufficient fall and winter rainfall,
while summer annuals respond to adequate amounts of
summer monsoon rains, blooming in late summer and
early fall when the rest of the desert plants are dormant.
Desert winter ephemerals typically live for 8 months, and
desert summer ephemerals typically live for 2–3 months.
During most years, the annuals are absent or few.
Rarely, perhaps once in a decade, above-average precipitation
triggers widespread germination of annual plants
which blossom into spectacular carpets of wildflowers. One
such event occurred in 2005, causing millions of tourist to
descend on Death Valley to view the breathtaking spring