September is a month of change in the garden. The air feels fresher, mornings are misty, and the golden evenings remind us that autumn is on its way. But don’t hang up your gardening gloves just yet — there’s still plenty to sow, plant, and do around the garden to keep it thriving right through to winter and set yourself up for a beautiful spring.

🌿 Seeds to Sow in September

Even though summer is fading, the soil is still warm, making September a great month to sow certain crops.

Quick Harvests

If you want something to perk up your autumn salads, try sowing:

Spinach – grows quickly and thrives in cooler weather.

Radishes – peppery, crisp, and ready in just a few weeks.

Salad Leaves – winter-hardy mixes like rocket, mizuna, or lamb’s lettuce.

Overwintering Crops

September is the ideal time to get a head start on next year’s harvests:

Spring Onions – sow now and enjoy them in early spring.

Broad Beans – hardy varieties like ‘Aquadulce Claudia’ can be sown towards the end of the month in milder areas.

Garlic – plant cloves directly into prepared beds for a reliable crop next summer.

Flowers for Next Year

Don’t forget your flower beds — a little effort now means a stunning display later.

Sweet Peas – sow in pots and overwinter them in a cold frame or greenhouse for strong, early plants.

Hardy Annuals like cornflowers, calendula, and nigella can be sown directly outdoors for early blooms in spring.

🍂 Jobs to Do in the Garden This Month

September is also about tidying, planting, and preparing your garden for the colder months ahead.

Tidy & Prepare

Cut back finished crops and add healthy waste to your compost heap.

Give beds a good weed and mulch to lock in moisture and suppress growth over winter.

Clear fallen leaves from lawns and ponds to prevent them becoming soggy and compacted.

Care for Plants

Divide perennials like irises, Hostas, and day lilies to refresh old clumps and spread them around.

Plant spring bulbs (daffodils, crocus, alliums) so you can enjoy an early splash of colour next year.

Give climbing roses and summer-flowering shrubs a gentle prune to keep them healthy and shapely.

Prepare for the Season Ahead

Pop a net over ponds to catch falling leaves.

Give your tools a clean and oil before winter sets in.

Sow a green manure (such as clover or rye) to cover bare soil, improve fertility, and protect the ground.

🌻 Final Thoughts

September is one of the most rewarding months to be out in the garden. The soil is still warm, the air is cool, and the work you put in now will pay off with fresh autumn harvests and a colourful, flourishing spring. So grab a jumper, head outside, and enjoy this wonderful season of transition.