What to do in your allotment in December
Written by Lee Senior
After last month’s cold snap, my allotment has finally received the message that it’s time to go into sleep mode, but for us gardeners it’s not always so easy to switch off! I’ve been out making new raised beds and adding well-rotted manure to improve the soil. Our allotment site recently had a free delivery of bark chippings from a friendly tree surgeon so I’ve also topped up all our paths. Any good weather this month is a priceless opportunity to do the improvement work that there’s no time for in the busy growing season.
Now is a good time to think about a planting plan for next season. Root crops don’t like ground that has been recently manured, or they will split or fork. Any beds earmarked for carrots and parsnips should be given a year off manuring..
December is one of the quietest months of the allotment calendar. As well as planning, it’s a good time to browse the exciting range of new vegetable seeds for next year. There’s nothing nicer than sitting next to a fire thumbing through seed catalogues and making plans. Merry Christmas!
Lee’s allotment checklists for December
Image: Geranium F2 – Super Hybrid Mix
Allotment flowers in December
- Scatter hardy flower seeds that are about to go out of date around the plot. They’ll germinate in spring and surprise you with their random colour.
- Sow Geranium F2 ‘Super Hybrid Mix’ seeds under glass. They need a long season to give their best and, if you can provide frost-free conditions, they can be sown now. A minimum temperature of 18C is needed to ensure germination. Geraniums work well in mixed beds interspersed with vegetables.
- I sow sweet pea seeds on a warm windowsill in December for growing on in my cold greenhouse. Keep them a little on the dry side over winter and pinch out the middles to encourage more flowers when they start getting too tall.
- Despite the recent cold snap, there are still a few straggly and tired roses trying to bloom. They will benefit from a winter prune (depending on the variety).
- Provided the soil isn’t waterlogged, winter is a great time to establish a new hedge. Thorny shrubs such as pyracantha or rosa rugosa form a living security hedge which, when established, can deter thefts.
- Hardy cyclamen come to the fore this month and look lovely in shady locations. They take up very little room, even in full flower.
- There’s still time to plant last-minute tulip bulbs in the ground or containers.
Allotment vegetables in December
- I enjoy growing Pea ‘Anubis’ indoors on a bright windowsill. Harvest the pea shoots using a pair of scissors in just three weeks and a second crop should follow soon afterwards. Use a shallow seed tray with good drainage, half filled with damp compost.
- Mushroom kits can be a great way to get an indoor winter crop, too. They also make a great Christmas gift!
- A thriving allotment can produce an impressive range of vegetables for Christmas lunch! Last year I contributed homegrown cabbage, cauliflower, garlic, Jerusalem artichokes, leeks, onions, parsnips, potatoes, swede and of course the inevitable sprouts. Christmas Day sprouts are the only ones my eldest daughter will eat!
- Wild Rocket Dragons Tongue can be sown all year round and this cut-and-come-again crop can be very successful from winter sowings. Grow on a bright windowsill (without too much direct heat from a radiator) and your rocket will be ready to harvest within 4-6 weeks.
- Continue to make successional sowings of overwintering broad beans either in a cold greenhouse or cold frame. ‘Aquadulce Claudia’ is one of my favourite varieties and it hasn’t let me down in 10 years. Try ‘Luz de Otono’ for beds and ‘The Sutton’ for containers.
- Make sure that all brassicas have a net over them to protect them from attack by pigeons.
- Start off your exhibition onion seeds using a heated propagator to speed up germination. Show varieties need a long growing season to swell to huge proportions.
Image: Plum Tree – Beauty
Allotment fruit in December
- Bare rooted fruit bushes can be planted out this month as long as the ground isn’t waterlogged or frozen.
- Create a new strawberry bed this month. Buy bare root plants now or use rooted runners from your own plants.
- Plant bare root plum and damson trees, adding plenty of mulch made from rotted manure or organic matter.
- There’s still time to divide large clumps of rhubarb and replant, or give some away to gardening friends or fellow plot holders.
- The dormant winter period is ideal for tackling old and neglected fruit trees that you may have inherited when taking on a new plot. Winter prune your apple and pear trees by removing dead branches and crossing growth. The aim is to open up the centre to create a good airflow.
- Avoid the temptation to prune plum trees over winter. This will encourage the destructive and damaging silver leaf disease.
- Blackcurrant bushes should be pruned to ensure a regular supply of new wood and maintain cropping. Cut a third of the older, darker wood close to the base during the dormant months between November and February. This is a great job to do when the soil is too wet to work!
- Cut back autumn-fruiting raspberries to ground level.
- Fruit cages come in different shapes and sizes and you can even build your own. They’re very useful, and this is the ideal time to purchase one, especially if you’re planning a new fruit garden on your plot.
Crops to harvest in December
- If you’ve grown potatoes for Christmas, harvest them as soon as possible unless they’re in pots or under cover.
- Your autumn and winter cabbages should be ready to harvest this month.
- Brussels sprouts, leeks, Jerusalem artichokes and swedes should be ready to harvest too.
- Keep picking kale.
- Harvest your late season potatoes and remember to save a few for Christmas dinner!
- Pull parsnips as you need them – they should be lovely and sweet now!
Image: Brussels Sprout F1 ‘Crispus’
Image: Original Veggie Bed
General December allotment jobs
- Keep off beds this month to avoid compacting the ground when it’s wet. Use planks to spread your weight if you need access.
- Take hardwood cuttings to propagate woody perennials like roses or herbs like rosemary. Cut a finger-long length of stem just below a pair of buds. Bury the cutting up to two thirds of its height in a pot to root.
- December is a great time to do big jobs like maintaining or installing paths, building raised beds and changing your plot layout.
- If you’re looking for an allotment hedging plant, Pyracantha ‘Red Star’ is a great choice. With bright red berries that last well into winter, this variety has less thorns than some and is great for the birds.
- Turn compost over regularly to deter rodents.
- Dig over your soil on a dry day. This improves the structure and allows larger clods to break down in winter frost.
- Check your shed and greenhouse for damage, clean the windows and tidy inside. Apply a wood preservative while there’s no greenery in the way.
- Look after your tools. Sharpen and oil secateurs to keep rust at bay.
- If you’ve taken on a new plot, carefully plan the space. Start with where you want your shed, compost bins, and long term crops like asparagus and fruit trees to go.
Planning ahead
- Place your seed order for the coming year to make sure you get exactly what you want before stocks get low.
- Family asking you for Christmas present ideas? A heated propagator and some seeds from your newly made wish-list might fill your stocking rather nicely!
Image: Super 7 Electric Propagator
Suttons Seeds recommend these areas which may also be of interest.
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