Gardens Illustrated
© Alice Pattullo

September gardening jobs

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The start of the season of misty mornings is one of Aaron’s favourite times of the year. Here's the jobs you should get done in the garden in September. Illustration Alice Pattullo

Advice from our columnist Aaron Bertelsen, who shares the jobs you need to do in the garden in September.


Don't miss our pieces on the best flowers and plants for September, the gardens to visit this month and what to sow and plant in September.

Gardening jobs for September

Check your brassicas. If they have grown well over the summer, they may be touching the netting you put over them now, leaving them vulnerable to attack from cabbage whites. Check the undersides of the leaves for the little yellow eggs, and make your cage of netting bigger. It’s worth investing a bit of time now as you will need the netting through the winter too, to keep the pigeons at bay.

Parsnip foliage will be looking quite messy by now. I like to go through the rows and clean it up, both for aesthetic reasons and to make life harder for the slugs and snails that would otherwise shelter there.

Keep removing foliage from tomatoes, so the maximum possible sunlight gets to them. In previous years, I have been picking tomatoes well into October, and I really do think that taking the leaves off has helped to extend the cropping season and give us more ripe fruit.

Provided you have successfully avoided the attention of badgers, now is the time to harvest sweetcorn. You can tell when it’s ripe and ready to eat as the hairs on the end of the ears will turn brown. Eat it as quickly as possible, before the sugars start to turn to starch.

As long as plants are cropping, they will need water. I like to weed one day, and water the next, leaving the weeds on the surface to break down. If you water immediately, there is danger that the weeds will re-root.


As the season starts to wind down, you can stop regular feeding of plants, both in the ground and in pots. Maybe you could put the time this frees up to good use by turning that soft fruit in the freezer into jam.

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Having studied at Kew Gardens and spent two years at Jerusalem Botanical Gardens in Israel, Aaron Bertelsen is now vegetable gardener and cook at Great Dixter. His book, The Great Dixter Cookbook was published in March 2017.


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