Thank you all for taking an interest in this topic and thank you for your support - we are all here to make this forum a richer experience for everyone. As an ordinary gardener myself and the catalyst for this discussion, I hope that this comment is welcome.
In agreement with the admin (thanks for your speedy help, btw), whose judgement we requested and have adhered to, we only use our web-address in the signature line.
If we were to conceal our true identity on the forum, we would, in theory, be free to do something that would be a sinister abuse: by masquerading as a non-commercial entity, we could recommend and link to our nursery as though we were just a happy customer.
Geoff51, I really regret that you are feeling angry or frustrated by what you see as abuse of these forums. I hear your need for this excellent resource to be respected and supported by those who truly love to garden - I agree wholeheartedly.
I hope very much that you will trust me when I say that we all work for a nursery because we love gardening and (almost!) everything to do with it.
Edward & The Team