If the rains don't come one year, the seed simply remains dormant. The mechanism is a germination inhibitor. Unless enough rain falls to remove this inhibitor, the seed ignores the wetting. This assures that the developing plant will have enough water to complete its life cycle and develop new seeds before the next dry spell. This chemically patient seed may wait more than a year to germinate, but once it does, the plant will develop, flower, and fruit much more rapidly than a temperate annual would.
Creosote bushes ply another strategy.
These regularly spaced shrubs look as though human beings had planted them, because their roots produce toxins that discourage the roots of other plants from intruding on their growing space. The small creosote bush leaves are coated with a resin so that they lose little moisture to the air. These combined strategies make creosote bush the most prevalent shrub in the park and enable it to prosper in all North American deserts. Creosote bushes that grow along a road tap pavement runoff and may grow twice as tall as those one row back from the road. The chief indicator plant of the Chihuahuan Desert is lechuguilla, appearing as a clump of dagger blades protruding from the desert floor.