Contributing gardening editor Marianne Alexander’s handy checklist of essential chores to do in December
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1 Continue to deadhead, feed and water bedding plants. If you’re buying new plants, look for heat-loving annuals such as zinnias, gomphrena, celosia, marigolds, hollyhocks and salvias that will cope with dry periods.
2 Nip out flower buds of foliage plants like sweet potato vines ( Ipomoea batatas), the polka dot plant ( Hypoestes phyllostachya), and coleus (now known as plectranthus). Feed with a high-nitrogen fertiliser. Cut back old flower stems of delphiniums and feed and mulch with compost for a further flush of flowers.
3 Feed repeat-flowering perennials like gaura, Shasta daisies, penstemons, perennial phlox, Inca and day lilies and dahlias with granular 2:3:4 or 3:1:5 or liquid manure. Stake dahlias and nip out the first buds. Cut back old leaves and flower stems of wild rhubarb ( Acanthus), then mulch.
4 Prune roses that only flower once at the beginning of summer. These include banksias, Dorothy Perkins and old-fashioned species or heritage roses like the moss and Galicia roses, Albertine and New Dawn.
5 Top up mulches where necessary. Use organic mulches which also improve the soil such as coarse weed-free compost, mushroom compost, husks, pips, nut shells, pine bark nuggets, straw, shredded leaves and bark chips.
6 Keep hydrangeas moist and mulch. When picking for the vase, choose those flower heads where the centre of each bract is fully open. Cut into the woody sections of the stem and stand in water overnight before arranging.
7 Green up lawns for the festive season in summer-rainfall
Hydrangea areas by feeding with a high-nitrogen fertiliser, for example LAN or 4:1:1, and water well. In dry areas, or if you are going away, hold back on feeding or use a high-potash fertiliser like 2:3:4; only water when necessary.
8 Water gardens in areas suffering from drought, in the morning or on cool afternoons, keeping to the water restrictions in your area. Rather than sprinkling the whole garden, target only those plants that are in dire need.
9 Pull out old dry leaves from clumps of red-hot pokers, spring-flowering watsonias, wild iris ( Dietes spp.), fairy fishing rods (dieramas), cordylines and
New Zealand flax. Look out for new Inca and day lilies.
10 Trim hedges and topiary. Give autumn-flowering subshrubs like indigenous wild ginger ( Tetradenia riparia), salvias and Orthosiphon and Syncolostemon species a light prune; this will encourage new growth and more flowers. Cut back wisteria by about a third.