And you can always use Google. For example, searching for:
site:www.gardenersworld.com/forum "hollie-hock"
Shows some 294 pages which have your name on them.
You do need to click on "do you mean hollie-hock" (otherwise it thinks you want articles about hollyhocks).
And you can add additional qualification if you want to find a particular post. That's far quicker and simpler than trying to wade through the text of 100s of posts.