September is a turning point in the garden. There is still plenty of colour to enjoy, but cooler mornings and shorter days are a reminder that autumn is on its way. It is one of the best months for taking stock: tidying tired areas, making small improvements and setting the garden up well for the months ahead.

Make the most of late colour

Many perennials are still looking their best in September. Rudbeckias, echinaceas, sedums, asters and ornamental grasses can keep borders full of colour and movement well into autumn.

Deadhead spent flowers where it improves the display, but don't be too quick to cut everything back. Seedheads and grasses can provide structure through winter, as well as food and shelter for wildlife.

Refresh pots and borders

Remove tired annuals as they fade, clear fallen leaves and pull out weeds before they have the chance to set seed. It is also a good time to divide and move herbaceous perennials, especially where clumps have become overcrowded or have outgrown their space. This will help to maintain their vigour and keep them youthful!

Adding compost or a good soil conditioner around established plants will help feed the soil and improve its structure ahead of next spring. 

A good layer of mulch, of around 2 inches, will help to keep those pesky weeds away.

Think ahead to spring

September is the time to start planning spring bulbs. Daffodils, crocus, alliums and tulips can be planted in borders and pots over the coming weeks, creating colour from the first signs of spring right through to early summer. Just hold off a little longer before putting those tulips in, the cool temperatures will do them the world of good.

When planting in pots, use a free draining compost and make sure containers have clear drainage holes. A few bulbs planted now can make a big difference when the garden is still waking up after winter and tide you over to the full herbaceous display to come.

Look after the lawn

Early autumn is an excellent time for lawn care. Scarifying, aerating, overseeding and top-dressing can all help revive tired grass while soil temperatures are still warm enough for seed to establish.

Keep mowing if growth continues, but gradually raise the cutting height as the weather cools. This will leave the lawn stronger going into winter.

A little thoughtful work now will help your garden look cared for through autumn and give it a much better start next year.

Bring in pelargoniums

Before the first frost, move pelargoniums in pots to a bright, frost-free place for winter. While you are doing it, take a few healthy cuttings from your favourite plants - an easy way to keep them going and add to next year’s display.