Posted: 02/03/2014 at 17:48
Hi siamcat - there's a Garden Gallery thread for posting general pix of our own gardens, and if you look at the forum topics you'll see a general list of places to put different threads. For instance, you mention design, so you could put any questions under the Design heading. You'll see threads with titles like 'what can I put in a shady border by a garage?', so you might just put that under Plants.
That said, you'll find if you just ask have a query about something, it won't really matter where you put it, as long as the heading is clear enough!