If you look at the ask a question page, there is a bit of disconnection from the actual ask a question forum. At the time you ask the question it's not very clear that the question will be posted in a public forum and I think this can add some unnecessary confusion as to in what form the answer will be delivered. I wouldn't be surprised if some posters has a different idea of what an "expert panel of gardeners" is and therefore doesn't expect or even want a public forum discussion around their problem/question, so they may not return for that reason also.
I haven't seen the notification the question asker gets after they finish posting the question, so not sure how it looks. However I'm thinking it would be better that the poster understood what to expect and where to go for answers before the question was asked, rather than having an afterwards explanation.
