http://www.london.diplo.de/Vertretung/l ... reich.html
If you are a spouse of an EU or German national or if you have had a Schengen visa from the German Embassy London issued within the past 12 months you may apply by post. In addition to the required documents please add a self-addressed "Special Delivery" envelope and the visa fee in postal orders. Please be aware that application by post can take eight working days.