Cut back herbaceous perennials (plants that die back in the winter and re-appear in the spring) that have finished flowering. This make the garden look tidier and discourages diseases attacking old growth. If on some plants the flowers have finished, but the foliage is still green and attractive, leave it until it is really blackened by frosts. Cutting everything down can leave unsightly gaps in the borders and should be avoided until as late in the autumn as possible. Any soft growth that has been cut down, such as geraniums for example, can be consigned to the compost heap or ‘green bin’ if you have a collection in your area.
Lift and divide established perennial plants. These are the plants which are not trees, shrubs or bulbs – they tend to make up the flower garden. The name basically means plants that survive for many years. Dividing perennials regularly will ensure healthy, vigorous plants that will continue to perform year after year. It also offers the opportunity to multiply your plants. If you’re not sure, older clumps are easily spotted, as all the young, vigorous growth is towards the outside of the clump and the centre is bare. Dividing can be done from now until spring, so long as soil conditions allow. My rule of thumb is if the soil is so wet it sticks to your boots, keep off it. Late flowering perennials like Asters (Michaelmas Daisies) are best left until spring before being divided. Lift plants gently with a garden fork, working outwards from the crown’s centre to limit root damage. Shake off excess soil so that roots are clearly visible. Divide by pulling apart by hand or by separating with a garden fork or spade.
Reduce the frequency of mowing now. Raise the height of the cutting blades in the mower as grass that is cut too short over the winter will not stand up to the poorer weather conditions and will be more likely to become infested with moss and weeds. Rake out thatch, aerate and top dress lawns. The autumn overhaul of your lawn will make a great difference to the grass after a summer of hard use. If you have larger lawns to deal with, powered machines can easily be bought or hired to help with all of these jobs.