What to Sow in September

September can feel like a turning point in the garden. The days are getting shorter, evenings are cooler and some of the summer crops are beginning to look rather tired.

But I don't think of September as the end of the growing season. There's still plenty you can sow.

For me, it's about making the most of the space that's becoming available. As one crop finishes, I'm looking at the gap it leaves behind and wondering what I can put there next. Some September sowings will give you something to pick within weeks, while others will sit through winter and give you an earlier start next spring.

What to Sow in September at a Glance

Vegetables: Radish, winter lettuce, corn salad, land cress, perpetual spinach, pak choi, mizuna, mustard greens, turnips, spring onions and overwintering onions.

Herbs: Coriander, dill, flat-leaved parsley and chervil.

Flowers: Calendula, poppies, California poppies, cornflowers, nigella, larkspur and other hardy annuals.

Under cover: Spring cabbage and a range of perennial and biennial flowers.

Empty beds: Green manure.

You certainly don't need to sow all of those. A couple of short rows, a few pots or one patch of autumn-sown flowers is plenty.

Vegetables to Sow in September

Salads and Quick Crops

September is a good time for a final few sowings of radishes and quick-growing salad leaves. They're ideal for filling gaps where earlier vegetables have finished.

You can also sow winter lettuce, corn salad and land cress for leaves through autumn and, with some protection, potentially into winter.

I find it much more satisfying to have even a small amount of fresh salad growing outside than to decide the vegetable garden has finished simply because summer is over.

Spinach and Oriental Greens

Sow perpetual spinach, pak choi, mizuna and mustard greens.

These are useful autumn crops because they're relatively quick and versatile. Pick young leaves for salads or leave them to develop and use the larger leaves for cooking.

The cooler weather can actually help here. There's much less chance of everything rushing to flower before you've had a chance to eat it.

Spring Onions, Turnips and Overwintering Crops

Turnips are worth sowing into gaps, while winter-hardy spring onions such as White Lisbon Winter Hardy can establish now and give you an earlier crop next spring.

September is also a time to think ahead. Depending on the variety, spinach, winter lettuce, kale and overwintering onions can all be started now for cropping later.

Not everything we sow has to give us an immediate harvest.

Herbs to Sow in September

There's still time for a few herbs.

Try sowing:

Coriander
Dill
Flat-leaved parsley
Chervil

These can provide fresh leaves before colder weather really slows things down. Perennial chamomile can also be started in pots or trays for planting out later.

I'd keep sowings fairly small. At this time of year, a pot or short row is often all you need.

What to Sow Under Cover

If you have a greenhouse, cold frame, cloche or somewhere reasonably sheltered, you can stretch the season a little further.

Protection isn't always about keeping plants warm. Keeping young crops away from heavy rain and the worst autumn weather can make quite a difference.

Spring cabbages such as April and Durham Early can be sown in modules in early September and planted out once they're established.

Again, this is very much about thinking ahead. You're sowing now for something you'll enjoy next year.

Flowers to Sow in September

There are plenty of flowers you can start in September too.

For direct sowing outside, try:

Calendula
Annual poppies
California poppies
Cornflowers
Nigella
Larkspur
Ammi majus
Poached egg plant

Autumn sowing gives hardy annuals time to establish before winter, and they can then get away quickly when conditions improve in spring.

You can also sow flowers such as hollyhocks, violas, lupins, aquilegias, verbascums, heleniums, perennial salvias, hardy geraniums and delphiniums into pots or trays and keep them somewhere cool and sheltered over winter.

There's no need to push them into lots of growth. We're simply getting plants established ready for next year.

Don't Leave Empty Ground Bare

If you've cleared a summer crop and don't have anything else planned for the space, consider sowing a green manure.

Green manures cover otherwise bare soil, help suppress weeds and can contribute to maintaining or improving the soil.

I've become much more conscious of this over time. Growing isn't only about what we can harvest — we also need to look after the soil we're asking to produce everything.

If I Were Choosing Just Five Things to Sow in September

If that still sounds like an enormous list, I'd make it much simpler.

Radish — for something quick to harvest.

Winter lettuce — for fresh leaves as summer crops disappear.

Perpetual spinach — for a productive crop that can keep going into cooler weather.

Cornflowers — an easy autumn-sown flower for next year's display.

Green manure — if you've got an empty bed and nothing else planned for it.

September is really about keeping the garden moving. Some things you sow now will give you something within weeks. Others will sit quietly through winter before getting going again next spring.

So when a space appears, don't automatically leave it empty until next year. Sow a little of something useful and see what happens. That's often how some of the most satisfying autumn growing starts.