The scientist who corresponded with Mendel about his pea experiments was Carl Nägeli. Nägeli was a Swiss botanist whose work focused on plant anatomy, cell division, and pollination, and he was one of the better-known botanists Mendel could contact in the 1860s.
Mendel wrote to Nägeli after completing his pea experiments and sent him information about his results. Their correspondence lasted from 1866 to 1873. Nägeli was interested in Mendel’s work but did not fully recognize its importance, and he encouraged Mendel to investigate hawkweeds, or Hieracium, rather than continuing with peas.
The hawkweed experiments produced confusing results because many Hieracium species reproduce through apomixis, an asexual process that can produce offspring without normal fertilization. This biological difference made Mendel’s laws appear less generally applicable than they actually were.
A common mix-up is Hugo de Vries, who independently rediscovered Mendel’s work around 1900. Nägeli, however, was the contemporary botanist who exchanged letters with Mendel during Mendel’s lifetime.