I've actually had foam hold up fine in clay if you prep the ground right first.

Forgets how much dust it shows.

My first year gardening I killed three lavender plants because the tags said full sun, but our Texas sun just fried them. I learned to check my actual yard's light at different times before buying anything. It made a huge difference, hugowells, and now I mostly bring home plants that actually live. I keep a little notebook in my shed to track what works in each shady or sunny spot.