In September, is can often feel like a race against time for tomatoes to ripen to red before the first frosts in your area. In a polytunnel, you will usually have a little extra time compared to plants that are grown outside, but you may still be wondering, this month, how many of the fruits will have time to ripen fully on the vine. The good news is that there are things that polytunnel gardeners can do to speed up the process. Here are some things you can do to encourage green tomatoes to ripen:
Cut Back on Watering To Get Full-Size Green Tomatoes to Ripen
Over the summer months, watering has been of utmost importance. If you have watered well and consistently then you will likely be rewarded with an excellent tomato harvest. But now it is time to treat your tomatoes a little worse than you have been doing. It may go against the grain, but if you cut back on watering, leaving your tomatoes a little too dry, they will put their efforts into ripening the tomatoes already on the vine.
Give Plants a ‘Haircut’ To Focus Energy on Ripening Green Tomatoes
Another way to encourage tomato plants to focus their energy on ripening green tomatoes is to give them a good ‘haircut’. Cut back the lower foliage on your plants, making sure to get rid of any dead, damaged or diseased material as quickly as possible. It is also a good idea to cut off any flowering heads, as these will, in any case, not have time to mature before the end of the season. When all extraneous material is removed, more energy will go into ripening green tomatoes already on the vines.
Startle Plants To Shock Green Tomatoes into Ripening
This tip may seen a bit brutal, but giving your tomato plants a bit of a fright can also spur them on a bit and encourage green tomatoes to ripen. You can shock your tomato plants by giving them a slight pull to shift their roots. This will send a signal to your tomato plants that they better hurry up and produce viable seeds to ensure their survival.
Speed Up The Process By Placing Bananas Beneath Tomato Plants
Bananas, and other ripening fruits, give off ethylene. This gas speeds up the ripening process, so placing over-ripe bananas beneath tomato plants will speed up the tomato plants and allow you to harvest a few more red ones before the end of the season.
Give Your Green Tomatoes More Time By Introducing Extra Protection
In a polytunnel it is possible to extend the season for your tomatoes, and give them a little more time to ripen on the vine. While tomatoes will ripen a little off the plant, they will generally have a better flavour if they are allowed to ripen fully on the plant. To protect your plants from autumn chills, cover them will a mini polytunnel, cloches, row covers or horticultural fleece.
If you want to know more about growing tomatoes, check out the other information in our handy guides and articles and let us know how you ripen green tomatoes in the comments below.
Elizabeth Waddington is a writer and green living consultant living in Scotland. Permaculture and sustainability are at the heart of everything she does, from designing gardens and farms around the world, to inspiring and facilitating positive change for small companies and individuals.
She also works on her own property, where she grows fruit and vegetables, keeps chickens and is working on the eco-renovation of an old stone barn.