Sometimes there is no wall to write a message on, should you then write on the back wall? Or do players somehow switch their walls off as they don't want players writing anything?

Unfortunately, this happens when a garden blocks you or you have blocked them Tracey.

Really? Oh dear, I can water but not post a thank you then?
I don't think I have anyone blocked anymore.
It must be annoying if someone has blocked you but you can still spot things in their gardens.

I guess a block means you can still water but superblock means you can never water.

Correct! A superblock means you can’t access someone’s garden at all!  It’s also permanent; not even support can reverse that option.

If you click on the mushroom (top left hand corner), you can bring up a box menu with an icon for checking who you have blocked.  It doesn’t state who has blocked you though.  Xx

Although the block means that you can't post or see what has been written on a garden wall, you can still water and find what you might be looking for. I understand that it is to reduce potential harassment or name calling but it seems odd to me that if the problem is the style of watering or watering without leaving a message why the block has been placed, that it does nothing to remedy that. I know that a super block can be performed but that seems a bit excessive.

Just more thoughts on blocking...if I am unaware of what has been posted on a garden wall...it could bring about some wrath from another player due to my not noticing that they have laid a claim and others have urged them on. Imagine finding the special prize and all the potential discontent.

Even then, though, Mary, you wouldn't have done anything wrong.  It literally states in every public garden that anyone may water at any time.  If the GO wants only certain people to spot, they must make their garden "frieds only" to do so.  It's not your fault, or your problem, if you can't read walls.

That said, I don't water where I'm blocked.  I want no interaction at all with those who have blocked me, any more than I do with those I've blocked.

Sometimes it is innocent...in that a blank garden wall is in front of you...and you just think...what a great player this one is to clean up their walls after responding. It is something that I aspire to do, but seem to get off track in doing so. And then the deed is done...and I go to post...and can't. I don't have anyone blocked...I have three superblocked though due to actions in my garden that I just could not tolerate for my visitors to experience.