Ripening tomatoes is something that most people growing tomatoes end up doing. Due to our climate it is not at all unusual to be left with tomatoes that haven't ripened.
Preparing for the end of the Season
From September on, any new flowers are very unlikely to come to anything. So, toward the end of the season remove any tiny tomatoes, flowers and foliage. This will allow the plant to concentrate its energy on the bigger fruits. It is best to leave the fruit on the vine for as long as possible. However, fruit will not ripen below 10° C (50°F). or above 29ºC (85ºF), as carotene and lycopene will not be produced and the tomato will not turn red. The high temperatures are generally not a problem in the UK. But when day time temperatures are this low its time to step in and help them to ripen.
Ripening Tomatoes - How long does it take?
How long they'll take depends on how red they are already. Tomatoes ripen from inside out so when you see the skin turning colour, the inside is already well on the way to being ripe. As a guide:-
Half red tomatoes - 7 days
Red only on the ends - 14 days
Pale green - ripen if given the right conditions (see Methods below)
Dark green - if they haven't matured then they will not ripen. To test this cut one in half. if it has yellowish interiors and jelly-like or sticky tissue, then it could ripen. But if not then its better to use these for making chutney.
Did you know:?
This is just for info a there is not much you can do about the weather turning against you and being left with green tomatoes! But, there is a stage in ripening called the "breaker stage," when the tomato is half green and half red. Once the tomato reaches this stage it seals itself off from the vine stem. From this point on, the tomato can be picked and ripened indoors without losing flavour. Your green tomatoes will be sweeter if picked after the breaker stage.
Ripening tomatoes - top 5 methods
Method 1 : Newspaper & Cardboard box
If the tomatoes are dirty then wash them gently and air dry. Wrap the tomatoes individually in newspaper and store in a cardboard box at between 14° and 21°C. The lower you keep the temperature the longer they will take to ripen. So if you have a large number you may wish to store them in different boxes and places so that you don't get them all ripening at once. Check the box weekly to take out any ripe ones and get rid of any that are starting to go mangy.
If you are impatient then speed ripening by adding a couple of apples to your box. They will release ethylene which will help the tomatoes to ripen.
Method 2: Paper Bag
This one is probably better for cherry tomatoes. Who wants to wrap those little suckers individually - not me! For this method, place your tomatoes in a paper bag with a ripening banana (yellow with green ends). Loosely seal it to keep the gas in. As with the apples in Method 1, doing this should help ripen your tomatoes. If the banana really starts to rot before the tomatoes ripen then replace it with a new banana. You can also do this in a jar with a sealing lid instead of a paper bag but you can't cram the tomatoes in as they will bruise so unless you only have a few tomatoes it is probably better to use a paper bag.
Method 3: Hanging the plant
If you have room, simply cut off the leaves and dig up your tomato plant. Shake off the soil and hang it upside down in a cool dry place like a garage out of direct light and leave to ripen. Check regularly and bring a few into the warmer house to ripen quicker when needed.
Method 4: Bring on the Stress!
As you reach the end of the season, take off all the leaves and then make a cut through the roots with a shovel. This will stress the plant and make it react as if it is under attack (which it is!) and it should bring on rapid ripening. Some gardeners swear by this 'shock' method.
If this feels too violent for you then a careful pull upwards at the bottom of the stem will disturb the roots below and may also work to signal the plant to ripen the fruit.
Another way to stress the plant is to cut back on water - just make sure that the soil doesn’t get too dry or the next time you water, skins may split.
Avoid feeding late in the season as any feed with excess nitrogen will slow the ripening process.
Method 5: Socks!!
Place your unripened tomatoes in woolen socks and store in your wardrobe! And then do let us know if this works because we have no evidence that it does!
How to avoid this problem next year
The question is how do you avoid this happening next year? The answer is to get yourself a longer growing season with more "tomato friendly" conditions. Haxnicks can't control the weather but we do have a number of tools to help with this.
The Twist Up Tomato Cloche
Once your plants are ready to go out into the garden why not use the Twist Up Tomato Cloche to give them their perfect growing environment.
You can use it over plants in pots or in the ground. For both it will lengthen your growing season by allowing you to put your plants out earlier than you would if they were unprotected. The Cloche, evens out temperature changes and, apart from taking it off for a short spell for pollination, your plant will be happy in it all season. It really comes into its own at ripening though. Each ripening fruit releases ethylene which helps the other tomatoes to ripen. If its windy then this gas is blown away without affecting the other fruit. In a Twist up Tomato Cloche the gas is trapped and helps all of your fruit to turn a delicious red.
Tomato Crop Booster
If you really love your tomatoes then this is a great way to grow them. The poly cover gives all the advantages of the Tomato Cloches when it comes to ripening but the main advantage is how the frame supports the plants. Properly supported plants are able to concentrate their energy into fruit production leading to a much greater yield of tomatoes. Giving them the conditions they need throughout the season should mean far less green tomatoes to deal with at this time of year.
Grower Frame with Poly Cover
This is a quick, easy and affordable way to make the perfect, low maintenance, ‘grow your own’ space in any sized garden. And tomatoes love it.
Especially useful if you don't have a greenhouse as you can start your tomatoes off in it using the poly cover to give them the warmth they need to start well. You can then use the frame and cover over them in the final planting position. There should be enough space to grow all your other salad ingredients alongside them too and there is also the option of an ultra fine Micromesh cover if the weather gets too hot but you still need to protect from pests.