Corrugated edging, either plastic or metal, comes in a roll and you dig it in, taking an element of the soil out, pushing the edging in, then packing the soil back in behind it.
One of the most popular options is known as log-roll – a series of half-cut logs on wire that can be placed along the edge of a border. It’s simple and effective. You can place edging slightly below the grass level, meaning you can’t see it, but the grass can’t grow over it.
This is ideal if you want to mow over it. Other people leave their edging proud – you can’t mow over it, but a strimmer will keep it neat. Both techniques are practical.
Brick or stone is popular, either in traditional paving blocks or reused house brick. Clear a trench, place them in position then pack the soil back in behind them. Rope-top edging made of terracotta remains a good choice, especially in Mediterranean style gardens.