As the nights start to draw in and become cooler, your tomatoes will still be trying to put on lots of new growth and flowers.
In warmer climates this does not cause a problem as the fruits will have plenty of time to ripen, but in the UK, especially the further north you go, this new growth will only serve to weaken the plant and the existing trusses of tomatoes may not ripen in time.
Spend time pinching out the tips to stop upward growth and watch out for those little side shoots, which should be nipped out to put all the plant’s energy into the fruit trusses it is already carrying.
If The side shoots are pinched out earlier in the year such as June or even early July, you can try popping them into a glass of water…roots will form quite quickly allowing the plant to be potted on and creating a new plant from your cuttings.
Tomatoes are incredibly greedy feeders and to avoid the plant using too much on leafy growth, I remove some of the lower leaves which also has the benefit of allowing more light in and air to circulate.