Gardening Column – September 2025
THE START OF AUTUMN
SUMMER is drawing to a close and autumn is just around the corner – what a perfect time to think
about planting – the soil is warm and autumn rains will get plants established before winter sets in.
September is a great planning month providing gardeners with time to reflect on their growing
season successes and to think about what to do in the coming year. It’s also time to start planting
spring bulbs. If you plant as many bulbs as you can get into the ground now, your efforts will be well
rewarded with a great show come springtime. The joy about bulbs is that once planted you need do
nothing else to them and you can choose old and new favourites to brighten up and bring colour to
your garden as it leaves winter behind.
Keeping colour in borders for as long as possible is top of the ‘to do’ list for September, so you
may like to consider incorporating late summer or autumn flowering plants such Asters. The name
Aster comes from the ancient Greek word for ‘star’, although they are often referred to as
Michaelmas daisies because of their typical flowering period in the autumn.
Asters come in blue, purple, red, pink and white each with a yellow centre, and in a variety of
sizes from 30cm to over 2m tall. They are good cut flowers and are easy plants for beginners to try in
the garden.
One of the most popular is Aster × frikartii ‘Mönch’ which is highly valued for its long flowering
period, producing an abundance of lavender-blue daisies with golden-yellow centres from
midsummer through to mid-autumn. It’s a variety that is perfect for pollinators, brightening up
borders or containers with minimal maintenance and growing to around 70cm tall.
A slightly smaller purple flowering perennial, also loved by bees and butterflies, is an old-
fashioned herb that is gaining in popularity – hyssop. It has beautiful dark green small pointed leaves
with blue-purple spikes of flowers and is great as a shrub or a low growing flowering hedge. It also
flowers in late summer and early autumn and its Mediterranean origins means it can cope well with
dry soil. Herbalists recommend hyssop tea to help relieve respiratory infections, the common cold
and sore throats.
In addition to some garden planning for the next growing season, top tips from the RHS for
September jobs in the garden include:
Collect and sow seed from perennials and hardy annuals
Divide herbaceous perennials
Stake tall late-flowering perennials, such as asters, for added support
Dig up remaining potatoes before slug damage spoils them
Net ponds before leaf fall gets underway
Keep up with watering of new plants, using rain or grey water if possible
Start to reduce the frequency of houseplant watering
Clean out cold frames and greenhouses so they are ready for autumn use
Cover leafy vegetable crops with bird-proof netting
Plant spring flowering bulbs
And finally …
“Autumn seemed to arrive suddenly that year. The morning of the first September was crisp and
golden as an apple.” J. K. Rowling
