I have rigged up a Heath Robinson style irrigation system in me
greenhouse; it is a collection of tubes and a water butt and a timer
and lots of pokey little bits of plastic and about 4million bits of
hozelock. It kind of works but in order to ehhh fine tune it (fine
tuning is a bit overstated; change that to: in order to avoid killing
all 20 tomato plants or flooding the entire housing estate), I wondered
if anyone had even rough guidelines as to how much water a tomato plant
needed per day in a greenhouse. It is delivered in a very slow dribble
to the base of each plant.

Des in Dublin by the sea.