Papaver rhoeas
Wilks was extremely interested in the phenomenon of hybridization. As secretary of the RHS, he organized several conferences on hybridization. It was in the third conference that Wilks organized that Bateson coined the word "genetics". Wilks' most famous horticultural work concerned the breeding of the Shirley poppy. Wilks noticed an unusual poppy in a corner of his garden ("abutting on the fields"). This was a minor variant of the wild poppy, "Papaver rhoeas", in which the petals were bordered by a strip of white. From this slight variation, by patient crossing and selection, he bred the varied and ornamental "Shirley poppies".