Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
nourish [ˈnʌrɪʃ] vt (feed) пита́ть (impf) (fig, foster) взра́щивать (взрасти́ть*perf)
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.