Help...attachments odd problem w rotation

[Dr. Dave 4u]

I'm not sure if this is the right forum to ask for help with my problem.

I take my orchid pics with my iPhone, lets say portrait or vertical format.

Then email them to my desk top mac where I download them. They look fine.

Then I write my post and attach the pic...
When I preview my post the pic is always rotated 90' to the left and is now sideways or landscape view.

So I delete it form the post's preview, open the pic on my mac in "Preview" app where it looks fine. Then using the rotate tool I rotate it four times bringing it back to the vertical where it started. I save the changes to the pic file. (changes ? its still the same vertical pic!)

Then I upload it on the orchid board, attach it to the preview and the re preview it and its fine so then I just post.

Anyone have any idea why I have to rotate the pic 360' back to the way it was and then it posts properly?

I am finding this more mysterious than the orchids life cycle!!

?????????