Parsnip!

Never eat anything bigger than your own head, they say... Challenge accepted. (Average sized parsnip included for comparison.)

These parsnips were planted in early spring. Parsnips can be a bit tricky - they can take a month to germinate (so don't give up on them too soon) and they need to be gently thinned when young to a good spacing for the grown-up plants. Keep them well weeded too, particularly when they're small - they don't cope well with competition.

Apart from that fussing, you'll also need to just leave them alone until winter - and they'll taste even sweeter if they've frosted in the ground once or twice.