How to ripen leftover 'stubborn' green tomatoes in September with 'foolproof' method

As we head deeper into September, many gardeners grow frustrated as their tomato plants still cling to clusters of green fruit that haven't had time to ripen. With the first frost approaching, cooler weather slows the tomatoes' ability to develop their full colour and flavour on the vine.

Due to this, most gardeners assume it's best to remove the fruit before frost begins. However, a specialist from Gardener's World recommends trying this "foolproof" method to ripen tomatoes on the vine first and then turning to a reliable indoor technique to ensure none of your crop goes to waste. Here's how it works and why it's ideal for September weather.

How to ripen tomatoes in September

1. Remove unnecessary flowers

To begin, the expert recommended removing any flowers on the vine that have no fruit. They said: "In your vegetable patch or greenhouse, remove any remaining flowers from your tomato plants. These have no chance of developing into fruit, so nipping them off now will help channel the plant's energy into ripening existing fruits."

2. 'Top' your tomato plants

By autumn, you should still see some trusses of fruit being formed. To help these ripen fully, gardeners should "top" their tomato plant by cutting off the main stem a couple of leaves above the uppermost truss of green fruits.

Popular garden creator Jamie Walton, also known as @nettlesandpetals,took to Instagram to explain the process of 'topping' and shared: "By cutting off the main growing point of the plant, it redirects its energy to ripening the fruit it already has rather than continuing to grow."

This practice is especially valuable in climates like the UK, where summers are short and cool, and the risk of blight increases when late summer turns to early autumn.

3. Harvest indoors

Finally, when temperatures begin to drop, it's time to harvest your tomatoes and move them indoors. According to Plant Maps, most areas in the UK will receive the first frost in late November - but this varies depending on your area.

To ripen any leftover green tomatoes quickly indoors, the expert at Gardener's World advised: "One tip is to keep them in a drawer or paper bag with a banana.

"The banana will release ethylene, a hormone associated with the ripening of fruit, which will help speed up the ripening process. Check the drawer or bag regularly and remove ripened tomatoes as and when you find them."