I think it means you can make a list of plants in your garden.

You have to click on the tab that sais 'Your Options'
Then in the drop down menu, click on 'Add Plants'

Put in the name of a plant in your garden, and click on 'Add Plant' lower down the page.

When you add a photo of a plant, you can 'link' it to the one in your garden page.
Like this :-

Click on 'Edit photo'
Click on the arrow alongside 'Not a picture of anything in my garden.
You'll see a drop down menu with the names you added to your garden page'.
Click on the name that corresponds to the photo.
Click on 'Add Photo'

That's it ! :)
It sounds more complicated than it is ...

Thank you Hywel. It's a shame sites don't explain this sort of thing for us oldies!

You can't be old ? ;)

Well, I'm certainly not going to send you a photo to prove that I am! Depends what you call old, though. Over 30? Most definitely and some.

You're in Wales, aren't you? N or S? My parents came from the South and I mostly consider myself Welsh even though I haven't lived in Wales. The closest was the Welsh Marches when we were in Hereford.

30 is ancient ! ;)
I am in my 60s so I am doubly ancient ...
There are one or two photos of me somewhere on here.

Yes I live in Wales - in the south west, not far from Llandeilo and Carmarthen.
My grandfather used to say he was English, although he was born in Wales ... because his parents were from Devon :)