I have been told that these two cannot cross pollinate, but I planted a Gherkin plant on a fence next to a muskmelon plant. The Gherkins are growing and providing lots of fruit. The muskmelon plant gave me what first looked like large Gherkins, same coloring, texture, and then the skin turned to the same texture as a muskmelon. When one got to the size of a large coconut I picked it and cut into it. What was inside was a cucumber! It has seeds like a muskmelon, but it has the taste of a slightly sweet cucumber. Have you ever heard of this before? I have several growing now. Picture shows size compared to a nickel, with the muskmelon leaf on the left and the gherkin leaf on the right.