Update....
The chillies are still going great, although I'm a little upset as one seems to have a bacterial infection. Leaf mould. Will pop some pics up soon. I have multiples of most but only one white bhut jolokia and of course Sod's law said it had to be that one. I haven't chucked it yet, isolated and stripped the worst affected leaves. I'm not holding out much hope but you never know.
Tomatoes all germinated well but now seem to have frozen in time. They are warm with heaps of light yet they just don't seem to want to get their first true leaves. Seed leaves and about an inch and a half tall. Been that way for a week I guess.
Planted up some other bits and they are doing great inside. It's a little early but did some more toms, basil, coriander, sweetcorn, squash and pumpkins, and a couple of different courgettes. I will sow another batch in a few weeks to be on the safe side.
Up at the allotment, potatoes are in (as well as garden) put in a few rows of carrots, beet root, parsnip, peas, broad beans and my MIL has sewn cauli, leek, sprout and some sweet peas. It's early but again, the weather has been taunting me!
LL......the irrigation system...
Basically, it's just the bin in the posts above, or a water butt or any type of reservoir really. The plumbing doesn't get any more complicated than what can be seen attached to the water butt and those pipes run straight to the aqua valves. I have two trays of pots, so two valves. They were 9 pounds each. Could easily do something on a much larger scale.
I don't think it will be quite as effective as regular watering for individual plants as they require, but as I'm away mon to fri, I think they will work great.
As a test I have already got soil in the pots and it's staying nicely moist, not water logger, but not drying out in the polytunnel which has been around 20 degrees the last few days.
One thing I have noticed is the water level in the bin (which will eventually be a weak feed solution) has been dropping a bit quicker than I would have liked due to evaporation but I think that can be massively reduced by adding either some bricks/stones/gravel around the pots meaning less water sitting in the tray or by some sort of cover for the trays which as another experiment will probably take the form of pieces of plastic sheeting sitting on the waters surface, like Lilly pads I guess. Either way, I will post up how I get on.