You have to start chitting potatoes as soon as you get them really. It is to stop them getting those long white shoots which fall off if you look at them. If you put them in the light then they make small dumpy shoots which are much more robust and will not fall off when you plant them. I'm hoping that JMB don't send me my seed potatoes until quite late because then I don't have to bother storing them by chitting for very long.
My two Crystal tomato seeds have germinated and I am molly coddling them. I know that the seeds were free but who puts two seeds into a seed packet?