Carol at May Dreams Garden speaks to the relevance of writers such as Mitchell whose time has past. If being a joy to read is not enough then maybe the very points made, considered irrelevant, will spur us to think past what is currently trendy and seek what "is of relevance" to the individual garden and gardener.
Mitchell suggests that when we find a garden or scene that appeals to us, that we should look closer than the focal point that catches our eye, and see the whole picture.
I have read this advise elsewhere and used it to good results.
Trees and shrubs standing tall, vines growing up then dangling, large leaves with distinct shapes , strong form in grasses and foliage like iris leaves and rattlesnakemaster,plants that mound neatly or stay low, lush green interrupted by color, changes through the seasons, all are choices to make the garden,as Mitchell says "personal and fascinating, because there is no such thing as dullness when the gardener is going full steam ahead and damn the torpedoes, as it were."