When did gregor mendel perform his experiments with garden peas? a. in the 1860s, the same decade as the united states' civil warb. in the 1760s, predating the formation of the united states of americac. in the 1620s, the decade in which william shakespeare diedd. in the 1720s, the decade in which bach composed the brandenburg concertose. in the 1820s, the decade in which ecuador became independent from spain