September is an ideal time for a great garden tidy-up, while it’s still warm enough to work outdoors comfortably before the inevitable freezing weather sets in.
If you’ve returned from holiday to withered summer bedding and dried-up pots, bite the bullet and empty them on the compost heap, replacing them with a spring display. Plant bulbs, pansies, heathers and other winter and spring stalwarts to brighten up your outlook.
If you’re not going to use your containers for winter displays, clean them out, wipe them down and put them away. Don’t leave terracotta pots out or they may succumb to frost and crack.
Some gardeners tend to be more relaxed about pest and disease control at the end of the season, but ignore them at your peril or you may be storing up problems that will remain dormant until next year. Cut off or prune out affected parts of diseased plants and burn or dispose of them so that overwintering spores won’t survive until next year.
Pest control is also important. Be aware that many biological controls become less reliable when the temperature drops as the predatory insects which provide the control then multiply more slowly. Take off shoots on plants which are infested with greenfly or blackfly and dispose of them.
Don’t leave garden debris lying around because slugs will shelter under it and are still capable of doing plenty of damage to your plants. It’s also important to keep up with the weeding because otherwise they are likely to shed seeds, creating a hotbed of more weeds next year.
Continue to deadhead roses and cut back finished summer-flowering perennials, removing supports which propped up the plants which have stopped flowering. These can be cleaned with a mild detergent and put away until next year.
The vegetable garden should still be producing rich pickings of French and runner beans, salad crops, courgettes and sweetcorn, but if you have time, clear away spent crops to create vacant rows, dig over the ground and refill the spare space with autumn and winter crops as soon as possible.
Give the greenhouse a spring-clean, emptying it of staging, plants and rubbish and give it a good clean with hot, soapy water, which will help flush out pests and diseases and prepare the area for any overwintering tender plants you may need to house. Remove greenhouse shading to allow in more light.
If you’re putting plants back in there, try to space them out to allow good airflow around them which will help stop the build-up of diseases such as soft rot and mildew.
Garden furniture can also be cleaned at this time of year on fine days, to save you a job next spring. Teak furniture can be washed with a mild mixture of soap and water and it is recommended that you use a soft utility brush to remove surface dust and dirt. Rinse the furniture thoroughly after cleaning and allow it to dry completely before putting it away for the winter.