Hi there, i have just started remodeling our garden and need to build a wall approx 6ft long x 1 meter high. The problem i have is im not sure which blocks i need to use. Can i get away with lightweight blocks or do i need to use concrete blocks. They will be rendered anyway so my bricklaying wont be seen luckily. Also can i lay them on edge or woukld it be best to lay them flat, it will be holding back a small amount of earth. I have not been a member for long but hopefully this will be a great site for information.
You don't say where you are located, but for walls to last, they need a good foundation. If you are in the northern half of the US, that means deep footers, or that wall will shift or fail over time. Since it is not a high wall, you may get by with just digging down and starting with a row of block/stone.