If it is properly made, a concrete path looks attractive alongside cultivated beds, and it should be weed free.
Alternative edge details are shown: a) with the concrete cast against a plank, and b) with a brick edging laid on a concrete foundation. The concrete surface can be made far less harsh in appearance if the hosing and brushing.
A concrete thickness of 75 mm (3”) is normally recommended for garden work but this can be reduced to 50 mm (2”)— thus saving some of the backbreaking labour—if
i) a layer of polythene sheet is laid over theor base material;
ii) a layer of chicken wire is laid over the polythene; and
iii) if the maximum length between joints is restricted as described in the next paragraph.
Concrete shrinks as it dries and will inevitably crack if cast as a path (or kerb) in long continuous lengths. You should therefore provide joints at a maximum distance apart of 2.4 m (8’) for the thicker type, or 1.8 m (6’) for the thin type. Cast alternate panels of your path as a first operation and then fill in the missing sections later. It is best, however, to ‘express’ the joints (that is, to leave a small gap between them) by leaving the shuttering plank in position or by using a wedge-shaped fillet that can be removed so that the joint can then be filled with mortar. If the path is longer than 20 m (65’) you should introduce an expansion joint by leaving a clear gap of 2.5 cm (1”) between two adjacent sections.