How the heck did that get there ?

Just as I was about to leave the dunes on Belhaven Beach to walk on the beach, I spotted this single rose plant hidden in the marram grass. They appear to be a variety of cultivated roses rather than wild ones and I wondered how they made their way across a wide salt marsh to these dunes. My only thought is that someone planted them there as a memorial for lost partner who was particular fond of this area of natural beauty.