Window Box Advice.
On a wider window ledge found in most older houses it ideally for
growing some small herbs and salad crops such as rocket,thyme,chives
ect.Its best to fix the container or window box to the window ledge
with screws or grip fix glue available from a builders merchant.Once
installed you are best to use a soil based compost such as John Innes
number 2 compost.One benefit of this is that the additional weight in
this type of compost makes the window box or container more stable and
also easier to water if the compost dries out.