In article , Janet Tweedy
writes
Not very practical in design ideas but i wondered if there was a way I
could attach some sort of hose to the tap on my very large waterbutt
and lead it into the greenhouse

Leaving aside that in most ways its best to use rain water from the
butt, my understanding from what I've gleaned, is that it is permissable
to fill up watering cans from a hose. Does anyone know for sure whether
this is the case? It seems to be quite difficult to get detailed
information on exactly what is and isn't allowed.

(My daughter suggested - if filling the can from the hose is allowed -
fixing the hose into the watering can and walking round the garden with
the hose permanently filling the can and the can permanently watering
the garden

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regards andyw