Ive done the quicker stuff...chantennay carrots, spring onions, dwarf leeks etc...just sowed a pinch of seed in a large plug tray and then, once germinated and grown on a little, i just transfer the whole plug to a bigger pot (or several plugs to a 10 litre pot)...no need to thin out and just harvest the clumps of veg when big enough.

I tried to do that Steveg and was not successful but lots of people do it successfully. I think you are maybe better using home made paper containers which disintegrate easily. I have used them for sweet peas. I used peat based biodegradeable shop bought ones for carrots and found they did not biodegrade too well.