When greening a facade, questions of style arise sooner or later: which plants and climbing systems are appropriate? Or vice versa: what can't be done? -- what does not work at all on my house or building? The answers depend a lot on the age of the building. The following sections deal with monument conservation and various stylistic epochs (eras) up to modern buildings. We provide suggestions and examples, and at the same time, an attempt is made to sketch a history of facade greening (source: Rudi Baumann, "Greened Architecture," Callway 1983). In this next section of Ideas, we"ll address types of greening and the dimensions of a greened wall area.