Poet-playwright's first novel; Sassafras, Cypress and Indigo, by Ntozake Shange. New York: St. Martin's Press. 222 pp. $10.95.

This is the first novel from the poet-playwright best known for her Broadway success ''for colored girls who have considered suicide/when the rainbow is enuf.'' Its three title characters, sisters who hail from Charleston, S.C., explore different ways of gaining emotional distance from ''the misery of the slaves who were ourselves.'' Sassafass is a poet and weaver, Cypress a dancer, Indigo a mystical stay-at-home who talks to her dolls and ''can't think of nothing but make-believe.''

The book is a celebration of woman's resourcefulness and resiliency. The variegated form - letters, recipes, and ''cures for what ails you,'' interwoven with straight narrative - faithfully suggests the several conflicting dimensions of the sisters' busy lives. So do their encounters with big-city travail: political protest, drug addiction, and sexual experimentation (much of it explicitly presented). Yet this novel successfully sidesteps almost every pitfall it digs for itself. Ntozake Shange has been described as an absolutely original American writer. That sounds about right to me.