December tasks in the garden
Try & get into the garden when the weather is dry, it is a good time for pruning, & any bendy stems from dogwoods or hazel can be used as a base for a homemade wreath which can be decorated with evergreens & berries. Use late afternoons & evenings to plan ahead for next year’s display; summer flowering bulbs are simple & easy to grow or try growing some colourful annuals from seed.
Plant up colourful displays in containers near the house using small evergreens, winter pansies & berrying shrubs or buy some indoor flowering plants which will last longer than cut flowers & also make a great gift - see our article on Indoor Plants for Christmas Colour & Scent if you want some tips on watering & positioning your plant.
Planting & Sowing Tips
- Plant bare-root hedging, there are a range of possibilities depending whether you want to create colour, an effective barrier or encourage wildlife, or all three!
- If the soil is not too cold & wet there are a number of shrubs that can be planted now. Plant winter-flowering Clematis cirrhosa & fragrant winter shrubs like Daphne bholua or plant shrubs for winter colour such as Pyracantha or Cornus.
- Sow alpine seeds now as they like a period of cold to start germination.
- There are a range of seeds that can be sown so that plants are well established before spring - Pelargonium, begonias & half hardy annuals such as snapdragons.
- Get organised & get your orders in from specialised growers supplying plants that crop early such as cauliflowers, cabbages & lettuces.
If you didn't get your pruning done last month it can still be done now.
- Coppice trees and shrubs such as hazel although Corylus avellana (Contorta) is grown for its attractive stems & can just be pruned to keep its size.
- Prune Acers and birches before Christmas to avoid the 'bleeding' that would occur if pruned in spring.
- Prune deciduous trees and shrubs, but leave Magnolias until summer and Prunus species until they are in leaf.
- Winter pruning of fruit trees and bushes can also be carried out this month. This will often involve spur pruning of apples and pears to let in more light and don’t forget to prune out any damage from apple canker which causes cracks and lesions. Bush fruit can also be pruned at the same time, for example blackcurrants, redcurrants and gooseberries. Also prune ornamental and edible grape vines before Christmas to prevent excessive sap loss.
- Prune back the longer growth on roses to reduce the damage from wind rock. Also make sure you prune or tie in long growth on climbers.
- Prune deciduous hedges that are overgrown such as beech.
- When tidying the garden keep wildlife in mind. A pile of leaves or logs will provide a valuable over wintering habitat for lots of small creatures or have a go at making a home for wildlife such as hedgehogs, overwintering bees and other insects.
- Insulate garden taps and any exposed pipework against extreme cold weather.
- Clean old pots and seed trays ready for next spring & clean down your greenhouse & staging to remove over-wintering pests.
- Cover rhubarb crowns with a forcer or bucket to produce earlier, sweeter stems.
- Net all brassicas to protect against damage from pigeons and earth up Brussel sprout stems to give extra support.
- Keep putting food and water out for the birds. Check your feeders more frequently, especially if there has been very bad weather. See our article on feeding the birds.
- Whilst repotting line pots with bubble wrap for winter protection and cover the surface of pots with decorative grit. Raise containers onto pot feet to prevent waterlogging. If you have terracotta containers in your garden move them into the garage or store room to help prevent them from cracking in the freezing temperatures.
- Clean moss & lichen off your paths.
- Pack the branches of tender woody plants with straw or dry grass then cover with fleece and mulch. For more borderline-hardy herbaceous plants such as Agapanthus and Phygelius cover with a thick mulch to protect them over the winter.
- Place cloches over any tender plants or herbs that like dry feet over winter such as Greek oregano and basil.
- Apply winter washes to fruit trees to control over-wintering pests.
- Check stored tubers of dahlias and cannas for signs of rot.
- Keep container grown plants such as bay trees & Camellia out of cold winds and protect to prevent the root ball freezing.
Lawns Maintenance Tips
- Avoid walking on the grass if the soil underneath is frozen as it can ‘break' and kill off the grass. You see the effect of this in spring when the damaged patches become brown and bare.
- If the weather is mild you may still need to cut the grass ensuring the blade height is about 2-4cm. Once the final cut has been completed it is worth considering having your lawnmower and grass cutting equipment serviced before the following spring.
Indoor Gardening Tips
- December is the perfect time to introduce winter indoor plants for example Poinsettias, Cyclamen, African Violets, Chrysanthemums and Azaleas. The key to being successful with these indoor plants is to ensure that they never dry out, that their very fine root systems are always kept moist and that they are put in a position where there is an adequate amount of light, no draughts and no exposure to excessive heat from radiators.
- Bring remaining tender plants into the greenhouse, conservatory or cool spare room.
- Reduce watering of houseplants and if they are looking a little unhappy try moving them to a sunnier windowsill. Don't forget to move susceptible houseplants off windowsills at night to protect them from the cold.
- Bring in Christmas bulbs such as Paper whites for flowering and keep in a cool place to extend the life of the flowers.
- Pinch out the tips of autumn sown sweet peas to encourage bushy growth.
- Ventilate greenhouses and conservatories on mild days and keep a lookout for over-wintering whitefly and red spider mite.