In September, GIY gardeners will continue to harvest produce and sow crops for Winter, but towards the end of the month we need to start to prepare for the colder weather. If you have fruit trees, make sure to pick ripe fruits before they are blown down. Summer pruning of apple trees should be finished this month as well. Other fruiting plants require attention too – continue to prune out the fruited canes of raspberry plants, and cut those to the base. Make sure remaining canes are supported. You can also pot up any strawberry runners for next year. At this time of year there is often a glut of plums – after exploring numerous recipes for using up the fruits, and once you’ve exhausted your options, they can be halved, stoned and spread out on a tray to freeze. Once frozen they can be stored in containers or bags until required. September is also a good month to order currant bushes.
We can continue to harvest sweetcorn, beans, tomatoes, potatoes and leafy veg like chard this month. Keep feeding your bean plants while they continue to produce, making sure to pick regularly. Once the plants have finished they can be cut down to ground level – if you can, leave the roots to rot down and enrich the soil. Consider the various options for storing your crops if you can’t use them immediately, to keep wastage to a minimum. Freezing, drying, pickling and storing whatever you can!
Cordon tomato plants should be pinched out at the tips to encourage concentration of energy on ripening the fruits. Towards the end of this month, when the temperature starts to drop, you can remove trusses of unripe tomatoes to be ripened indoors. Maincrop potatoes can be lifted, dried off and stored in hessian or paper sacks in a cool, dark place. You might want to consider removing the foliage a few weeks before lifting the tubers as this can help prevent blight spores infecting them in the process.
Pumpkins, squashes and marrows need a little attention in September. Removing any leaves covering the fruits can help them to ripen. It is also a good idea to raise them off the ground using a piece of slate or wood, to prevent rotting.
Looking to the colder weather, we need to think both about protecting our existing plants and sowing or planting for Winter crops. Onion and shallot sets can be planted this month, in a sunny spot 10cm apart and with the tips sitting above the soil. You can also sow kale, land cress, pak choi, mizuna, lamb’s lettuce and mustard. With the temperature dropping, it is a good idea to water greenhouse plants early in the day so that it is relatively dry by evening time. It’s also best to close greenhouse vents and doors in late afternoon to retain warmth, and towards the end of the month you can remove shading devices.
There are other jobs to be done in the garden to help support our wildlife. You should rake the thatch from lawns, aerate compacted areas and re-seed any bare patches. If you don’t have a wildflower or meadow area in your garden, you could consider starting one now. Once the ground has been well raked you can spread seed – make sure the mix includes yellow rattle, which suppresses otherwise overly vigorous grass growth and allows more delicate plants to flourish. Also ensure you use a native plant mix. It’s a good idea to place netting over ponds where there is a risk of leaves dropping into them – if you can, collect fallen leaves to create leaf mould, which is a very rich compost material. Cleaning out water butts and checking downpipes and connections is important in order to effectively store as much water as possible.