Literary and dialect languages influence each other and, as a result, mutual enrichment occurs, in particular in botanical vocabulary. Comparison of folk and literary floristic names in the Ukrainian language reveals: common names for literary language and dialects (with phonetic, word-formative, semantic variants in dialects); common names with different lexical meanings; many words with a broader semantic structure in dialects; figurative meaning of words in dialects; the existence of different lexemes to describe the same object in floristics; numerous names in dialects are represented by synonymous pairs; the influence of the literary language on dialects, and as a result formation of duplicates (lexical, word-forming, phonetic); dialect words and meanings that are part of the literary-normative ones; specific dialect words not used in the literary language; words known only to older people which, even in the speech of representatives of the older generation, have moved to passive vocabulary; names that are represented by a word in a literary language, but in dialects – by a phrase or even descriptively. Dialect names reveal greater lexical, phonetic, word-forming, semantic variability. The mutual influence of the literary language and dialects contributes to the improvement of the norms of the literary language, and appears to be the basis for the development of the national language.