It is native to northern California, Nevada, and the West Coast of the United States.

It can be found in mountain and foothill habitats, in shaded crevices and on steep slopes.

Phacelia rattanii is an annual herb growing 15 centimeters to one meter in maximum stem length, taking an erect, branching form.

The hairy inflorescence is a one-sided curving or coiling cyme of bell-shaped flowers each no more than half a centimeter long.

The flowers are white to light blue and are surrounded by calyces of sepals coated in long hairs.