Pull up your first parsnips
Start harvesting your parsnips. Pick every other one in the row to allow the remaining roots to get bigger before harvesting them much later in winter, when they’ll be sweeter.
If you need the space to grow something like a late crop of salad leaves or to plant onion sets, harvest all your parsnips. Remove the leaves and store the roots in boxes of sand somewhere cool and dark, ready to use during winter.