Basil Chupin wrote:

Don't use railway sleepers - they will rot within a reasonable period
(like around 6 years).

Err, my "sleepers" rotted out within 5 years. Helped by the termites
(why is that panel bowing outwards).

My railway sleepers have lasted nearly 10 years. Yes, they are slowly
rotting, but compared to the cost of "sleepers", I'm happy.


Use treated pine - sleepers or other sized planks.

Just a personal 2c, but I will not touch that stuff.
I garden to remove chemicals from my food. Not to add toxic ones.