The September Garden Reset: What to Cut, Keep & Leave Alone

September is a bit of a transition month in the garden. Summer is slowly winding down, but there’s still plenty of colour to enjoy and lots to prepare for the months ahead. It can be tempting to give everything a big tidy-up, but not everything needs cutting back just yet!

Here’s our guide to what to cut, keep and leave alone this September.

What to cut back

September is a great time to give some plants a little tidy-up after a busy summer.

Lavender – trim lightly after flowering to keep it neat and encourage a compact shape. Avoid cutting too far into old, woody growth.

Summer-flowering shrubs – once flowering has finished, some can be lightly pruned to keep their shape.

Dead or damaged growth – remove anything that is clearly dead, diseased or damaged.

Spent flowers – keep deadheading plants that are still flowering, especially roses and bedding plants, to encourage a final flush of blooms.

What to keep

Not everything that looks past its best needs to go!

Seed heads can provide food for birds and valuable shelter for insects over autumn and winter. Plants such as coneflowers, rudbeckias and ornamental grasses can look beautiful as they fade and add structure to the garden.

If your plants are still flowering, leave them to enjoy for as long as possible. There’s no need to cut healthy plants back simply because autumn is approaching.

What to leave alone

Some garden jobs can wait until later in the year.

Try not to cut everything back as soon as the first autumn leaves appear. Leaving some stems and foliage through winter can provide shelter for wildlife and protect plants from colder weather.

A few September jobs worth doing

Collect seeds from plants you'd like to grow again next year.

Plant spring bulbs such as daffodils, crocuses and alliums.

Move or plant perennials while the soil is still warm.

Keep watering newly planted plants if the weather remains dry.

Clear diseased leaves from around plants, but consider leaving healthy fallen leaves for wildlife or collecting them to make leaf mould.

Why we love a September reset

September isn't about making the garden perfectly tidy. It's about giving your garden a little refresh while preparing it for the seasons ahead. Take a step back, enjoy what's still flowering and make a plan for what you'd like to see growing next year.