What to Do in the Garden in September
Living North's gardening expert Ross Pearson shares his advice on what needs to be done in the garden as summer slides away
The garden notices long before we do. The swallows begin gathering on telephone wires like they’re holding tiny committee meetings about departure times. Spiders suddenly decide your front door is premium real estate. Mornings arrive wrapped in mist and every lawn glitters with dew as though someone has been out before dawn scattering diamonds around with reckless enthusiasm.
I love September; not because it’s dramatic, it really isn’t. It’s wonderfully subtle. July shouts. August sings. September leans in quietly and says, ‘you might want to start thinking about what’s next’. And for gardeners (or at least, for me), that’s strangely exciting.
The frantic pace of summer begins to ease. The pressure disappears. There is finally time to stand back and admire everything you’ve somehow managed to grow before frost, slugs or your own forgetfulness inevitably intervenes.
You also become astonishingly generous. Neighbours who politely admired your courgettes in June are now avoiding eye contact in case you try to give them another six. Friends receive tomatoes whether they asked for them or not. Family members open the boot of the car only to discover you’ve hidden a pumpkin in there ‘because I had a spare’.
September is the month where the garden starts paying you back. Every apple feels like a small miracle. Every handful of beans seems completely unreasonable considering they all came from one tiny seed. You find yourself eating meals that are suspiciously home grown simply because the garden has become impossible to ignore.
There is also something wonderfully satisfying about knowing you’ve made it. The seedlings survived. The late frosts did not win. The pigeons were only partially successful. And somehow, despite everything, you’ve ended up with flowers, vegetables and enough memories to carry you comfortably into autumn.
If gardening had a victory lap, September would be it.
Japanese Anemone
Every garden needs one dependable friend. That is the Japanese anemone. Just as many summer flowers begin looking slightly exhausted and in desperate need of a holiday, Japanese anemones stroll onto the stage carrying elegant white or pink blooms on tall, graceful stems. No panic. No drama. No need for staking or feeding. Just effortless beauty.
They dance in the lightest breeze and somehow manage to make an entire border feel fresher than it did a week before. Even better, bees absolutely adore them, often queuing politely for a turn. Well... as politely as bees ever queue.
Planting
Japanese anemones enjoy moist but well drained soil in sun or partial shade. Give them room because once they’re happy, they tend to settle in rather enthusiastically. They are wonderfully reliable but not especially good at respecting personal boundaries.
Care
Water during prolonged dry spells in their first year and cut stems down once flowering finishes in autumn. Every few years lift and divide large clumps if they become too adventurous.
Collect rainwater
Summer droughts have a remarkable ability to make us promise we'll install six water butts ‘next weekend’. September is next weekend. Clean gutters, reconnect water butts and prepare for autumn rain. Future you will be incredibly grateful during the next dry spell, even if present you would rather be drinking tea.
Plant autumn flowering crocus
It feels deeply confusing planting crocus while summer flowers are still blooming, but trust the process. Autumn flowering crocus appear just when you least expect them, bringing little bursts of colour as everything else begins slowing down. Gardening often requires faith bordering on optimism.
Rescue pot-bound plants
Have a look underneath containers. If roots are escaping through drainage holes with the determination of prison break specialists, it's time to repot. Fresh compost and a slightly larger home can completely transform a tired plant.
Give lavender a gentle tidy
Don't hack it back brutally. Just trim away spent flower stems and lightly shape the plants while avoiding old woody growth. Lavender forgives many things. Heavy handed haircuts are not among them.
Photograph the garden
This sounds wonderfully lazy because it is. Walk around taking photographs of borders, containers and awkward corners. Come winter you'll have forgotten exactly what grew where and will spend hours wondering why you planted three enormous plants in the same tiny gap. Photographs settle many arguments between present you and future you.
Start thinking about spring colour
Garden centres begin filling with bulbs around now. Go in for one packet – come home wondering why you've somehow purchased enough daffodils to start your own public park. It happens to the best of us.
Leave some seed heads
Not everything needs tidying. Seed heads provide food for birds, shelter for insects and beautiful structure throughout autumn and winter. Besides, they look rather splendid sparkling with frost later on.
Sow winter salad leaves
Mustard, mizuna, rocket and winter lettuce all grow surprisingly well now. There’s something wonderful about picking fresh salad while everyone else assumes growing season has finished.
Try Chinese leaves
Pak choi, tatsoi and mibuna actually prefer cooler conditions. Sow them now and you’ll avoid many of the bolting problems that plague spring sowings. Sometimes doing things later works much better. A useful life lesson in patience.
Start a strawberry nursery
Rather than letting runners wander aimlessly around the allotment, peg healthy ones into small pots while they’re still attached to the parent plant. Once rooted, snip the connection. Free strawberry plants: the very best kind of mathematics.
Ripen squash properly
Before harvesting squash and pumpkins, leave them in the sun for around ten days if the weather behaves. The skins harden beautifully and they’ll store for months. Patience is surprisingly profitable.
Save tomato seeds
Choose your tastiest tomato. Scoop out the seeds, ferment them for a couple of days, rinse and dry. Congratulations – you’ve just become one of those gardeners who casually says, ‘I’ve been saving this variety for years’.
Experiment with green manures
Empty beds needn’t stay empty. Sow green manures such as phacelia or grazing rye to protect and improve soil over winter. It feels like putting your allotment to bed with a particularly expensive duvet.
Host an honest harvest
Gather everything you’ve grown onto one table; the triumphs, the disappointments, the vegetables that accidentally became enormous. Take a photograph. Gardening has a funny way of making us focus on what failed while completely ignoring everything that succeeded. September is a good month to remind yourself just how much you’ve achieved.
Final Thoughts
By September I become completely insufferable. Every meal somehow begins with the words, ‘these came from the garden’. Visitors are marched outside whether they expressed any interest or not. Complete strangers making the mistake of asking how things are growing receive what can only be described as an illustrated lecture.
I also develop a worrying inability to throw anything away. ‘That might make a nice seed head’, ‘those beans can probably become next year's seeds’, ‘I'm sure there's something useful I can do with 17 ornamental gourds’.
There almost certainly isn't.
September does that to gardeners. It quietly turns us into collectors, planners and slightly over enthusiastic storytellers. Every flower reminds you of when you planted it. Every apple has somehow become a personal achievement. Even the compost heap starts looking strangely impressive. And perhaps that's the real joy of this month.
Summer has not quite left, autumn has not quite arrived, and the garden sits comfortably between the two, offering one last glorious chance to slow down and notice what you've created.
Then, of course, you'll pop into the garden centre ‘just for a look’ and return home with 200 bulbs and absolutely no regrets. September wouldn't have it any other way.
Garden writer, and lecturer of horticulture and outdoor education leader, Ross has won seven RHS Gold Medal awards to date.
