Prune
Wisteria and shrubs such as
Pyracantha after flowering.
Hebes and lavenders can be given a light prune after flowering.
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.
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.
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.
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.
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 & 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.