Winter is on its way, leaves are falling rapidly, and wind and rain are on the increase. Remember winter can be a tough time for birds in terms of water and food, so keep supplies well topped up.
- Clear up fallen leaves – especially from lawns, ponds and beds.
- Raise containers onto pot feet to prevent waterlogging.
- Plant out winter bedding.
- Continue to cut down faded herbaceous perennials and add these to the compost heap.
- Ornamental grasses and bamboos can be cut back and tidied up at this time of year.
- It is still a good time to lift and divide overgrown clumps of herbaceous perennials.
- In mild weather, weeds will still appear. Hoe regularly to keep them in check.
Wet September and October weather will have made many clay soils unworkable until spring. In these cases, mulching will help to improve and maintain soil structure.
Make sure that you have not forgotten any of your tender plants and bulbs – they need to be brought inside or into a heated greenhouse over the winter. Protect alpines from the wet, if you have not done so already.
Hellebores rarely flower naturally by Christmas, despite their common name of Christmas rose. They can be encouraged to flower a little earlier, if you want, by covering them with cloches, potting them up and bringing them into a warm greenhouse, or placing them on a windowsill inside the house.
Large tubs that are at risk of cracking in the frost should be covered with bubble wrap, hessian or fleece, to insulate them over the winter.
Remove stakes and other supports as final late-flowering herbaceous plants die down for the winter.
Tidy up leaves from around borders. They can be added to the compost heap, or placed in separate bins to make leafmould. Some leaves, such as plane and sycamore, are slow to break down and can delay you using your compost if you mix them into the general heap. Leafmould makes an excellent soil improver, and can also be used as a seed-sowing medium.
Dig new flower beds as the weather allows. Don’t work on them when it’s very wet, as walking on sodden soil can cause compaction.
Watch out for downy mildew and black spot on winter pansies.
Check chrysanthemums regularly for signs of white rust.
Look out for crown rot and brown rots (sclerotinia) on died down perennials, especially if you are on clay or poorly-drained soil.
Be aware that many diseases will overwinter in the soil, or on plant debris. antirrhinum rust and delphinium black blotch, as well as sclerotinia, will lay dormant and re-infect plants when they come up the following year. It may be necessary to replant new specimens in another place if the problem is severe.
Michaelmas daisy mites on aster novi-belgii cultivars can be a problem. Other asters, such as aster novae-angliae cultivars and aster ericoides cultivars, have more resistance.
Grey mould or botrytis can be problematic in wet weather.
Do not feed plants this late in the season, as they are no longer growing and the nutrients may be washed into rivers and streams by winter rain.
Digging the soil, especially bare patches or newly cultivated land, will expose pest larvae and eggs to birds and frosts, as well as clearing weeds and improving soil structure. Don’t leave soil uncovered for too long, however, as it runs the risk of erosion and washing away of valuable nutrients. Black polythene sheeting will protect it in the absence of planting or mulch.
Protect newly planted trees, hedges and shrubs from wind and cold. A temporary netting windbreak is sufficient where there is no natural shelter.
Straw, bracken, or something similar can be used to pack around deciduous plants and protect them from frost. A wooden frame with clear polythene stretched over it can do a similar job without blocking light from evergreens, but don’t let the polythene touch the foliage, as condensation at these points could freeze, or cause rots.
This is also a good time to transplant trees and shrubs growing in unsuitable positions. However, if they are more than a couple of years old, you are unlikely to be able to remove an intact enough rootball to ensure the plant’s survival in its new position, and you may be best advised to leave well alone.
Pruning and renovation of many deciduous trees, shrubs and hedges can be carried out from now throughout the dormant season. It is easier to see what you are doing when the branches have no leaves. Suitable examples are fagus and corylus. Exceptions are tender plants, and also Prunus species (e.g. ornamental cherries, plums and almonds), as these are vulnerable to silver leaf if pruned in the autumn or winter. Evergreens are best left until the spring.
Lightly prune bush roses now, if not done already, as reducing their height will prevent wind-rock. Roses are generally shallow-rooted and can become loose in the soil if buffeted by strong winds.
Climbing roses should be pruned now at the very latest, and should preferably have been done much earlier in the autumn.
If your trees are too large for you to manage the pruning alone, then you may need a tree surgeon. Otherwise, take care not to damage the tree when sawing off thicker branches.
Tie wall shrubs and climbers onto their supports to protect them from wind damage. Any growth that refuses to be trained in this way can be pruned off.
Garden hygiene helps greatly in the prevention of disease carry-over from one year to the next. It is always a good idea to rake up and destroy (i.e. do not compost) any infected leaves. Diseases such as black spot on roses, scab on apples and pears and quince leaf blight can all be controlled to some extent in this way.
Toadstools are often visible at this time of year, and many people are concerned that they may be finding honey fungus. Honey fungus fruiting bodies (toadstools) usually appear on, or at the bases of, affected trees. Similar looking toadstools in beds or lawns are more likely to be harmless saprophytic fungi which live purely on dead material and pose no threat to garden plants.
Coral spot is often noticed once the leaves have fallen from deciduous hedges, shrubs and trees. This problem can be connected with poor ventilation and congested, un-pruned twiggy growth (as found inside clipped hedges), but it is more a sign of unsuitable conditions than a serious pathogen in itself.
Holly leaf blight is still uncommon but can be spread in wet weather.
Rabbits and squirrels can be a nuisance as the weather gets colder, gnawing the bark from shrubs and trees. Placing guards around new woody plants is advisable.
Damage from bay suckers may still be evident, although the pests will have been and gone. However, it is a good idea to remove affected leaves if there are only a few, and to take note to look out for damage next spring (usually around May) – the problem should then be treated promptly.
When pruning trees and shrubs, take the opportunity to examine branches for signs of disease. Small cankers, dieback, and rotten, hollow stumps at the centre of old shrub bases, are best removed early on before they spread.