Plant asparagus crowns in a trench that is one to two feet wide. Set crowns up to six inches deep and nine to twelve inches apart. Asparagus grows easily in any well-drained soil. Found growing wild on English riverbanks, delicate asparagus ferns were nicknamed “sparrow grass”. However, asparagus allowed to stand in water develops root rot, which can quickly destroy a complete bed. Asparagus roots have a tendency to “rise” as bed matures. Gardeners typically add soil to rows of a mature asparagus bed to keep crowns undercover. Asparagus is also susceptible to late spring frosts, which kill emerging spears Take care to keep your asparagus bed covered until frost danger is past.