How to Ripen Tomatoes on the Vine

Standard-sized tomatoes take 20 to 30 days from blossom set to reach full size--commonly called "mature green"; they take another 20 to 30 days to ripen, that is begin to change color. A tomato can be picked when it begins to change color--from green to red, pink, yellow, or orange depending upon the cultivar.

 

The optimal temperature range for tomato ripening is 68°F to 77°F; tomato ripening is slowed when temperatures are cooler or warmer than the optimum range. Tomatoes stop ripening when temperatures are less than 55°F and greater than 85°F. Once a mature green tomato has begun to blush or turn color, it can be brought to full color or full ripeness off the vine at room temperature--70°F to 75°F. A tomato will be equally flavorful brought to full ripeness on or off the vine--once it has moved beyond "mature green" to color change.

 

Estimated days to maturity, fruit size, and color can be used to estimate the harvest time for your tomato crop. Temperatures outside the optimum range can delay harvest. Tomatoes can not be forced to maturity more quickly than nature will allow. However, there are to expedite the tomato harvest when temperatures are right.

 

Once tomatoes on the plant begin to reach mature green, here's how you can quicken the overall ripening of fruit on the vine:

 

• Harvest daily. Pick fruit as soon as it starts to show color; this will allow other fruit on the vine to gain size and come to harvest more quickly. Tomato fruit picked at first sign of color can be ripened at room temperature. Fruit ripened off the vine will be just as tasty as those left to mature on the vine. Cut or gently twist off fruits supporting the vine at the same time. Don't leave overripe fruits on the vine; they decrease productivity and may spread disease.

 

• Remove flower clusters. Pluck new flower clusters from tomato plants that have already set fruit. Removing flowers will direct the plant's energy into ripening the fruit already maturing on the vine. Remove flower clusters no later than a month before the first expected frost to ensure fruit on the plant makes it to harvest without frost or cold damage.