After Pesach, Jews in Israel switched from mentioning geshem, rain, in the second blessing of the Amidah prayer, speaking of tal, dew, instead. As the rainy season ends, we no longer invoke God’s power to bring rain.
Outside Israel, however, Jews cease mentioning rain at Pesach, but don’t start talking about dew in its place. This is based on an argument of the poskim (legal commentators) about whether mentioning dew is necessary. Why the difference in opinion and practice? It could be that dew matters much more in Israel; in a dry year, it can yield more water than rainfall in the desert.
Or perhaps the difference is spiritual-psychological. Dew is gentle, almost imperceptible and ever-present; very easy to take for granted. Is it necessary to express constant appreciation for the countless blessings that we enjoy but barely notice?