These troughs have so many uses : instant hedging, controlling wandering mint, easy borders, as indoor gardens - and I expect you can think of a lot more uses !
They will last two to three years above ground, but will biodegrade more quickly in the soil.
Our troughs are about 50 cm long [ 20 inches roughly in old money ] and about 15 cm ( 6” ) wide at the top, and roughly the same deep.
When you fill them up, just pull the tie to hold everything neat and snug until planting time.
(Plants shown not included.)