Hugelkultur
The advantage with this technique is that there are lots trees on the periphery of our site so plenty of dead branches and logs and a local tree surgeon also delivers this as well as wood chippings. You can even use scrap wood. I found it interesting. She started by experimenting just with a big plastic bin with a wood layer at the bottom and is now making a full bed in the ground
https://www.growveg.co.uk/guides/how-to-make-hugelkultur-beds-for-growing-vegetables/