I have several plants I got this spring in the closer side of the L shaped bed. I buried the tags that came with them and also put a small stake by them so if I lose those I can ID when dug up. A plastic knife would work great too.
The soil in the long bed is from the Hospital lawn they dug up to expand the parking lot. There are huge chunks of sod in the left side so put some compost on top of it to let it break down over winter. The L shaped bed has some real nice composted manure from a ranch here that is about 30 years old mixed with some sand. The seedlings are loving it. I could see a difference the day after getting them in which was almost Sept. in that bed. The other long was was mid Aug.