I use model railroad materials and natural stones for the landscaping; the "flowers" are tiny pieces of bunka.
You can see the whole process of building this house, "from concept to completion," by reviewing the blog archive from the oldest to the most recent posting.
See the Tower House in person at the Chicago International miniature show, April 3 - 5, Marriott Chicago O'Hare, 8535 W. Higgins Rd., Chicago, IL. Visit the web sire at http://www.bishopshow.com/ for more information.