Agatha Christie Wiki

In the novel Nemesis, Colonel Walker is a retired military man, who goes on the Famous Houses and Gardens tour, together with his wife, Mrs Walker. In the past, Colonel Walker had mostly served abroad.

Colonel Walker is interested in gardening, and has a collection of fuchsias in his garden at home. During the course of the tour, he enjoys talking to Miss Marple about horticulture.

After the death of Miss Temple, Colonel and Mrs Walker decide to continue with the tour, as they do not want to miss seeing a particularly rare collection of fuchsias in the garden that is due to be visited soon.

When he says goodbye to Miss Marple, Colonel Walker promises to send her a cutting of the magnolia highdownensis, and one of the mahonia japonica, although he is not sure if it will do well where Miss Marple lives.