Can you place a heather on all your outgoing emails?

??

What's a heather? If your name Heather is you can configure a signature that will appear in all your sent emails, but I do not believe it's possible to attach a purple-flowered Eurasian heath that grows abundantly on moorland and heathland to an email.

It would be nice to receive an email with a heather attached though. I have never received one of those in an email, or in person for that matter.

Presumably you mean a 'header'.

What kind of header do you want to include, other than the email Subject line?

John, please try to make allowances for posters for whom English is not their main language.

A header!!! Of course.

I was going to suggest this, but I didn't think that was what the OP had in mind:

You can do this in your signature.

Mail Preferences/Signatures.