December grow your own
Sticking with the brassicas, the Brussels sprouts should be starting. You are allowed to eat them on other days as well as Christmas day!
Leeks should be about ready, just take what you need and leave the rest to stand until required. Leeks are much better harvested from the garden as they are required but in severe weather this can be difficult, so you can lift a few and heel them in on well dug ground, this will not freeze solid.
The carrots should come up for storage now if they haven't already, store either in peat or sand or even a traditional clamp.
Lift celery, parsnips and swedes although parsnips and swedes are very hardy and may be left if the ground is not needed. You can always cover them with fleece or straw to help stop the ground freezing them in.
Jerusalem artichokes will be available and you can start on Salsify and Scorzonera. Salsify is often called the 'vegetable oyster' and properly cooked is a wonderful vegetable.
It's worth checking any vegetables you have in store and removing anything that has started to rot before it spreads. Potatoes especially need to be checked and watch out for slugs that have emerged from a potato to go and damage another one.
Other crops you may have for harvest:
Perpetual spinach, celeriac, chicory (non-forcing and forcing varieties), endive, kale, kohl rabi, lettuce, winter radish, spinach, turnips.
Courtesy of www.allotment.org.uk