Later in the month there is a definite chill in the air, and our short summer is coming to an end. However, this can be a most beautiful time of the year. There is absolutely nothing more thrilling than a cool, sunny September morning. The plants seem to be standing to attention as if startled by the cold air, but the sun is glinting off them encouraging them to hang on for a while longer. And you can feel a change coming. There is something deeply exciting about that! It’s not the time to take your foot off the pedal, though. This is the time to prepare not only for the winter months but for next year’s garden too.
Sowing and Planting
The end of September marks the start of the season for planting out or moving shrubs. Remember to mulch them well afterwards.
Start planting your spring flowering bulbs. These can go in bare patches of the borders, under trees and into decorative pots, beneath your autumn and spring bedding plants. Crocus fritillaries and dwarf bulbs can be planted into lawns as well. Some people plant bulbs in aquatic baskets at this point which can then be dropped into the ground in the spring and easily removed after flowering.
You can also plant out hardy annuals for next summer.
Sow sweet peas in pots and keep them protected under cover for next year.
Broadbeans and hardy varieties of peas can also be sown for early crops next year.
If you want, you can start garlic cloves in pots to plant out in November, but you can always just wait until then.
Start to take cuttings from perennials such as salvias as insurance for next year, or simply for more plants!
You can also take root cuttings from hardy perennials such as Japanese anemones to increase your stock.
Pruning and Plant Management
Herbaceous perennials may be dug up, divided and replanted this month. This not only increases your stock, but rejuvenates the plants as well.
If you have tender perennials you can pot them up and keep them under cover to protect them through the winter.
Pot up your herbs as well and keep them indoors for use in the winter months.
Strawberry runners can also be potted up to propagate new plants and to replace older plants that are less productive.
Maintenance and Planning
As soon as the leaves start to fall, rake them up and keep them either in black plastic bags (with air holes punched in the sides) or in wire baskets to make lovely rich organic leaf mold for mulching your plants and enriching your soil in a couple of years time.
Save seed from your favourite plants and vegetables for either growing again next year, or for handing on to others. Dry the seed heads, scarify them and keep the seeds in envelopes in a cool, dry place – and remember to label them.
Buy your spring bulbs for planting in the autumn.
Clean up your greenhouse and line it with bubble-wrap to insulate it throughout the winter.
Aerate your lawn, raking out any moss, and give it lawn an autumn feed!