Full instructions on page 110.Concrete slabs look completely different with holes in them, through which small flowers can grow. It is even possible to cast such slabs to be used on a terrace, with their holes being perfect for low-growing plants, such as thyme.
Measure out the size that you would like your slab to be and fashion a mould of the same size. For optimum results, make your own mould using film-faced plywood and timber battens screwed together. This should make the mould easy to dismantle once the slab has set, so it can be used multiple times.
We have used a round plastic container for the hole in the middle, but you can use anything you like.
A slab laid on the lawn with blue squill.
Full instructions on page 110.