August jobs Top 10 jobs this month 1 Prune Wisteria 2 Don’t delay summer pruning fruits trained as restricted forms 3 Deadhead flowering plants regularly 4 Watering! - particularly containers, and new plants, preferably with grey recycled water or stored rainwater 5 Collect seed from garden plants 6 Harvest sweetcorn and other vegetables as they become ready 7 Continue cutting out old fruited canes on raspberries 8 Lift and pot up rooted strawberry runners 9 Keep ponds and water features topped up 10 Feed the soil with green manures Things to do this month in the veg garden 1. Make time to harvest your crops (and preserve them if necessary) 2. Give trained fruit trees their summer pruning 3. Sow green manures on any empty patches 4. Keep watering if the weather is dry: particularly containers and new plants 5. Collect seed from favourite varieties (not F1 hybrids) Trees and shrubs Pruning and training Prune wisteria and climbing shrubs such as Pyracantha after flowering. Prune wisteria and climbing shrubs such as Pyracantha after flowering. Hebes and lavenders can be given a light prune after flowering. Rambling roses can be pruned now, once they have finished flowering. Give hedges a final trim over now. They will only grow a little before cold weather stops growth. Get in qualified tree surgeons to remove large shrubs and trees that were casualties of winter waterlogging and summer drought. Remove stumps wherever possible, as rots could spread to other plants. General maintenance Continue to deadhead shrubs, such as roses, to extend flowering into early autumn. Spindly specimens that have lost leaves can be cut back a little further when deadheading, to encourage new growth. Thoroughly soak drought-stressed plants and shrubs, especially newly planted ones. Use grey, recycled or stored rain water wherever possible. Keep early-flowering shrubs such as Camellia and Rhododendron well watered during dry periods to ensure good flower bud initiation. Propagation Semi-ripe cuttings can still be taken to propagate many common garden shrubs (e.g. box, Ceanothus, lavender). Rhododendrons, azaleas and Clematis can be propagated by layering. Pest and disease watch Brown patches, needle loss and sooty mould on spruce (Picea) trees are evidence of green spruce aphid damage earlier in the year. Mid to late August is a good time of the year to apply biological controls for vine weevil. Grubs will be starting to hatch and soil temperatures are now suitable for the nematodes to be effective. Target vulnerable plants such as Rhododendron, Camellia and containerised plants including fuchsias. Black spot on roses is very common at this time of year, and spraying will no longer be effective. Clear fallen leaves and burn them to prevent spread. Powdery mildew can be a problem in dry summers. Leaf drop, disfigured and damaged leaves can be a symptom of weather damage. Flowers ’Sowing and planting Towards the end of August sow hardy annuals directly into borders. They will overwinter and flower next summer. Cutting back, pruning and dividing Cutting back the foliage and stems of herbaceous plants that have already died back (e.g. Dicentra) is starting to be a priority. Don’t neglect hanging baskets - deadheading, watering and feeding will help them last through until autumn. Deadhead plants such as Dahlia, roses and Penstemon and bedding to prolong the display colour well into early autumn. Don’t cut off the flowerheads of ornamental grasses. These will provide winter interest. Hardy geraniums can be cut back a little to remove tired leaves and encourage a new flush of growth. Prune climbing and rambling roses that do not repeat flower or produce attractive hips, once the flowers have finished. Propagation Pinks and carnations can be propagated by layering. Propagate irises by dividing the rhizomes if not done last month. Take cuttings of tender perennials such as Pelargonium and Osteospermum, as soon as possible. A greenhouse, cool conservatory or a light windowsill are ideal to bring them on until they are established. Rock garden plants, such as Helianthemum, Aubrieta and Dianthus can be propagated from cuttings at this time of year. General maintenance Feed containers, and even tired border perennials, with a liquid tomato food each week to encourage them to bloom into the early autumn. Keep picking flowers from the cutting garden to encourage more flower buds to form and open. Alpines that have developed bare patches of die-back, or have become weedy, can be tidied up by in-filling the patches with gritty compost. This will encourage new growth as well as improving their appearance. Most perennial weeds are best dealt with when in active growth, if necessary applying a weedkiller. Planning ahead Collect and store seed of hardy annuals and perennials for sowing later in the autumn. Good plants to try include Calendula, Nigella, Cerinthe, Papaver, Aquilegia and hardy Geranium. Buy or order spring-flowering bulbs. Some bulbs can be planted now, such as Colchicum, daffodils and Madonna lilies (L. candidum). Pest and disease watch Inspect chrysanthemums for the first signs of white rust and take immediate action. Remove and destroy any Nicotiana showing signs of downy mildew. This shows up as yellowish blotches on the upper surface of the leaves. Powdery mildew can be prevalent at this time of the year. Treat with an approved chemical at the manufacturer’s rates. Apply nematodes to control vine weevil grubs, in pots or the ground. Earwigs can make Dahlia blooms ragged. Set traps to reduce damage. Don’t be worried by bright green, heavily-armoured looking insects on your plants - these are harmless shieldbugs which do not require control. Distortion on Phlox could indicate the presence of phlox eelworm. Discoloured leaves on herbaceous plants such as Chrysanthemum, Anemone and Penstemon may be leaf and bud eelworm.