Plant winter tubs as soon as the summer bedding is cleared. Biennials like wallflowers are available as bare-root bundles right now in our garden centre here in Hereford, offering fantastic value: team them with cheery daffodils or tulips in matching colours for a display next spring which will take your breath away.
During winter itself there's a wide selection of plants which will give you plenty of colour to cheer you up even on the coldest days. Pansies are a perennial favourite and flower in all but the hardest of frosts. Tuck them in round evergreens like Euonymus japonicus 'Aureopictus', with green and gold leaves, or variegated box clipped into a handsome ball or pyramid.
For something more unusual, the early-flowering snowdrop 'Atkinsii' teamed with jet-black lilyturf, Opiophogon planiscapens, makes a sophisticated black-and-white combination; or for a shady spot, try the evergreen soft shield fern (Polystichum setiferum) or strappy-leaved hart's tongue fern (Asplenium scolopendrium) with th marbled purple leaves of evergreen heucheras like 'Palace Purple'.
Grasses are another lovely but low-maintenance winter container plant. The soft, airy textures of bronze-leaved Carex comans contrast well with sturdy evergreens like Hebe 'Red Edge' or winter-flowering Viburnum tinus 'Eve Price'. Simply plant them out in the garden once winter is over.