Gardener’s Diary: gardening tasks for September
Our resident vegetable grower, Claire Ratinon, shares her gardening tasks for September, from what to sow, harvest and maintain, plus what to cut back to ensure new growth ahead.
Claire: It’s September, the month most associated with gathering the harvest and celebrating the abundance that will hopefully see us through the colder months. As the month moves towards the autumn equinox and the Harvest Moon, the days will be getting steadily shorter so now’s the perfect time to pick as many beans and tomatoes as you can, and savour those summer flavours – maybe even preserving them to enjoy over winter.
Growing up, September was the month that truly signalled new beginnings to me and now I associate it with when the transition into the next cycle of the vegetable patch begins.
What to sow in September
Many of the seeds that I wrote about in August’s column – mustard greens, pak choi, endives and chicories – can still be sown in early September as there’s enough time for them to get growing and in the ground before the cold weather slows them down for the winter.
Another cool-season leafy crop that can be sown in September is lamb’s lettuce – also known as corn salad – which is a welcome addition to the salad bowl when the lettuces have faded. Originally considered a weed, its deep green, glossy leaves have a milder taste than the mustards and chicories that they’ll be living alongside and will grow (albeit rather slowly) all through winter. Seeds can be directly sown into soil or compost and then thinned out to give the remaining plants 10cm to 30cm between them, depending on the size of leaves you prefer. Sow these seeds now so they get growing before the days are shorter than the nights.
What to plant out in September
During September, the brassicas, endives and chicories that you sowed in August will be ready to be planted out. Once your seedlings have a few sets of true leaves, plant them between 20cm and 30cm apart, knowing that the closer together they are, the smaller the leaves you ought to harvest. If the plants are growing together with the closer spacing and are left to grow too large, they will end up competing with each other and be more susceptible to pests and diseases.
Gardening tasks
Even though the whiff of autumn is distinctly in the air, your summer crops – if they’re still going! – will be having their last hurrah and so keep picking regularly. Check your beans, courgettes and tomatoes every other day for ripe fruit and, after harvesting, water generously (and consider feeding with a liquid feed) to keep them productive for as long as the sun is warm and bright.
‘Stopping’ your cordon (indeterminate) tomato plants will lead to the plant diverting its energy to the fruit that has already been set, giving them a better chance of swelling and ripening before the weather really cools. Do this by removing the main growing tip above the last truss of developing tomatoes and keep on top of pruning the side shoots, which your plants will try to produce more enthusiastically once they’ve been stopped. Without this intervention and upkeep, you will finish the summer season with lots of smaller, green tomatoes which are good for making chutney from but since I’m not a fan, I try to avoid this fate at all costs!
Also consider stopping your winter squash vines too, for the same reason, by pruning the vines and cutting back excess foliage so the fruit are exposed to the sunshine. Encouraging your plants to concentrate their energy on the squashes that are growing and ripening already will give them a better chance of maturing thoroughly in time for harvesting which will deepen their flavour, and it enables the fruits to develop a more robust skin so that they store better over winter.
By the end of the month, your beans are likely to be on their way out. When you come to clearing the stalks, cut them down at ground level and leave the roots in the soil to decompose in situ as this will release precious nitrogen back to the soil, ready for whatever plants you’ll be growing there next.
