Winter Garden Maintenance tips. December

  • By Tony Jepson MCI Hort FdSc
  • 20 Jan, 2022

Get out into the fresh air on a rare mild day. December tips

- Continue to cut back faded herbaceous perennials.

- Rambling roses can be renovated with a hard prune now.

- Pruning and renovation of many deciduous trees, shrubs (including woody roses) as well as hedges can be carried out from now and throughout the winter.

- Prune apple and pear trees. Prunus species (including ornamental cherries, plums and almonds – fruit with a stone) are normally pruned mid spring.

- Cut back ornamental vines, ivy, Virginia creeper and Boston ivy.

- Clear weeds as required.

- Dig over soil on vegetable/flower beds if not already done - this will improve the soil.

- Tidy-up fallen leaves from borders if you have not already done so and add them to the compost heap. Leaf-mould can be used as a soil improver. Good garden hygiene helps prevent diseases.

- Grass will continue to grow if the temperature is above 5°C so it may be necessary to give the lawn a trim. Raise the cutting height.

- Tidy tubs and containers by removing weeds, debris and add a layer of decorative gravel/grit mulch. This will stop mud splashing up in wet weather.

- Raise pots onto ‘pot feet’ or bricks so that they don’t spend the winter sitting in wet puddles.

- Some large tubs may crack in the frost so you may want to cover them with bubblewrap or similar to insulate them over the winter.

- Check tree ties and stakes to ensure that they are still effective. Wall shrubs and climbers should be tied onto their supports to protect them from damage by the wind.

- Acers and Betula should be pruned before the end of the year to avoid sap bleeding from the cuts.

- Have you insulated your greenhouse with bubble wrap?

- Clear leaves and twigs from greenhouse and shed gutters.

- Rake fallen leaves from your lawn before they kill the grass.

- Regularly check the tubers of plants such as Dahlia and Canna you have stored for signs of drying out, dampness or rot. Remove dead bulbs before it spreads.

Planting

- You can continue to plant bare-root deciduous hedging plants and trees, move established deciduous trees and shrubs

- Its okay to plant roses but don't plant them where roses have been planted previously as this can lead to replant disease.

- Plant lily bulbs ideally in January.

- It is too late now to have plants with colour during the winter as they would need time to establish. So, visit public gardens, garden centres etc and take note of the most colourful - dogwoods (Cornus), Salix and white-stemmed Rubus shrubs and consider what would be suitable for a possible winter display in your garden next year.

Propagation

- In mild areas you can still lift and divide herbaceous perennials when the weather is dry. This will increase your stocks and revive any poorly flowering clumps.

- Bring tender plants into the greenhouse or your conservatory if not done so already. Even in mild areas the weather usually gets much harder after December.

- Root cuttings can be taken from now on and Alpines can be sown from seed this month (They need a period of cold weather to break the seed dormancy).

- You can take hardwood cuttings from ornamental shrubs such as Berberis, Buddleja and Forsythia.

- Propagate ornamental shrubs such as Cornus, Salix, Forsythia, Weigela, Escallonia, Rosa, Ribes, Chaenomeles and Elaeagnus by taking hardwood cuttings. You can also take cuttings of deciduous climbers such as Fallopia and Lonicera.

Treatments

- Spray a winter wash on roses and the surrounding soil to keep black spot under control.

- Place bark chip mulch around the base of your Christmas rose to stop mud splashing on the blooms.

- Watch for signs of lawn waterlogging as you may be able to remedy this with some, scarifying and a top dressing – ask us for advice.

Landscaping

- The winter is a good time to think about landscaping and new installations – while the garden is dormant and can cope with being dug up and moved. Consider garden lighting, water pipes, drainage and add lights and power points to sheds and out-buildings – of course, you will need an electrician.

- Are any pipes susceptible to damage from freezing? - drain them now and put lagging around outdoor taps so that you can use them throughout the winter.

- If the weather is dry you can still treat wooden structures with preservative.

- Ask us about new paving, fence building, pond digging, gravel, mulch borders, compost bins, arches, pergolas etc.

- Why not lay stepping stones to avoid walking on and damaging your lawn when the weather is wet.

- Stop paths becoming slippery by removing algae - you may need to buy a herbicide or use a pressure washer (obviously not if the water is likely to freeze)

- You can repair hollows and bumps in the lawn during mild spells by cutting an 'H' shape in the turf, peeling back the grass, and either filling with top soil or scraping away the soil if you have a bump.

Pond care

- Net your pond to stop herons stealing your fish.

- Regularly remove fallen leaves from ponds.

- Check water levels regularly to make sure that you have no leaks.

- Pond specialists may be selling-off last years stock cheaper - now might be a good time to look for pond pumps etc.