Garden Guide

How to ripen green tomatoes indoors
Oct. 16, 2013 @ 04:58 AM

The chill in the air has you looking at the tomato plants, and all of that green fruit hanging from them, and wondering if they’ll have enough time to ripen. Luckily, there is no frost in the forecast, and we’re supposed to get warm weather again, so you may have a bit more time.   

So when a frost is in the forecast, head out and harvest the green tomatoes. Any that are at least close to the size they’re supposed to be when ripe will come indoors to ripen. Those that are on the small side will also be harvested and used to make pickled green tomatoes or maybe green tomato chutney.

Some green tomatoes may be picked before the first killing frost and stored in a cool (55 F), moist (90-percent relative humidity) place. Do not store green tomatoes in the refrigerator since red color will not develop at less than 50 F. When necessary, ripen fruits at 70 F. Green tomatoes can be stored at 50 to 70 F for one to three weeks.   

Researchers in France have tested for optimum off-the-vine-tomato-ripening conditions. They used mature, still green, cherry tomatoes for the tests and found that storing in a well-lit place that doesn’t get very warm resulted in the highest concentration of seven carotenoids, including lycopene. These tomatoes were ripened at 70 degrees F in the presence of light and were tested six days after harvest when they were fully ripe. However, for a sweeter taste, it was found that those ripened at 79 degrees F had higher levels of sugars and lower acids.

The tomatoes should be red, pink or mature green, which means a glossy green without red. Tomatoes that do not fall into these categories will likely not ripen. Tomatoes can be saved in several ways. The ideal storage temperature is between 55 and 72 degrees. Only disease free tomatoes should be saved.   

There are a few ways to ripen tomatoes indoors:

Pull up the whole plant.

One method for ripening tomatoes is to pull up the entire plant, including the roots. Shake off as much soil as possible, and hang the plant, upside down, in a cool area that gets indirect light and allowed to complete the ripening process. ECA staff in Hyde County says an attic works well if temperatures don’t get above 80.

Ripen tomatoes on a windowsill.

Many gardeners prefer to place the fruit on a shelf or windowsill. If you’ve got tomatoes that are starting to turn color, this method usually works very well. Simply pick the tomatoes, wash them, dry them and set them on your windowsill to finish ripening. There’s some debate about whether you should place them stem-side down or blossom-end side down.

Store them in newspaper in a box.

If you have green tomatoes that are still pretty firm and not showing any color at all, you can try this method. Pick the tomatoes, wash them and dry them. Wrap in newspapers, place in a box in a single layer and store in a cool place. Tomatoes should not be allowed to touch. Store the box in a cool dry place, such as an unheated basement or garage. Check the boxes regularly for signs of ripening and remove those that are starting to change color so they can finish ripening on your counter top. The flavor won’t be as good as those you picked that were already starting to change color, but they’re still WAY better than anything you can buy in the supermarket, and this method can yield tomatoes for several weeks.

So, there you have them — three methods for ripening your green tomatoes indoors. Which one do you use?   

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