Spring bulbs should be planted from October through to December, commencing with daffodils and narcissi, whereas tulips are better planted in November and December. Make sure bulbs are planted at the right depth. Daffodils and narcissi need to be 3 inches below the soil, whilst tulips need to go down at least 6 inches. A container planted with a mixture of bulbs at different depths will extend the flowering period for several weeks. Tulips and wallflowers can make ideal companions often flowering about the same time. Wallflower plants are available from garden centres and market stalls and should be planted by the end of October, space them wide enough apart for tulips to be planted in between them later on. Winter pansies and primulas can also be planted this month. They can survive the coldest of winters and make an attractive addition to containers and borders. If containers with pansies and primulas are overwintered under glass in an un-heated greenhouse or frame they will flower sooner in the spring.
Once they have died back herbaceous perennials can be divided and replanted into their new positions. To give the best start plant them in well dug soil enriched with plenty of compost and a handful of bonemeal. The first frosts of winter take effect in October and can turn a colourful display of dahlias into a brown and sorry sight overnight. The stems should be cut back to just above ground level and provided they do not become waterlogged and frozen they may survive in place over the winter to flower another year. But to play safe they are better dug up and stored in a frost-free place over the winter, preferably in a container of moist compost to prevent them from drying out completely. Next spring they can be started off in trays of compost to produce shoots from which cuttings may be taken or they can be planted out directly in their flowering positions.
Give evergreen hedges their last trim of the year, but be careful to avoid cutting into the brown parts as they will struggle to come green again next year. Give rose bushes a trim to protect them from strong winds loosening their roots, but do not cut back completely as this should be done next spring.
In the vegetable garden tidy up the remains of summer crops such as runner beans, marrows and courgettes which give up once the nights turn cold. Consign as much waste to the compost heap or bin as possible and encourage the rotting process by covering with plastic sheeting or an old carpet to conserve heat and moisture. Ideally have at least two or more compost bins or heaps on the go so that the contents of one can be aerated by transferring from one to the other. In that way more heat will be generated that will hasten the composting process. Anyone doing this will soon discover that it is not only the compost that gets warm in the process!
Plant garlic and red onion sets in October and sow Aquadulce/Claudia broad beans in late November/early December as they are very hardy and will emerge in the Winter months unaffected by severe frosts, whereas other varieties are not recommended for autumn sowing
For more tips and advice see also the RHS Wisley Website January advice page