Tips for ripening tomatoes on the vine

Optimal Temperature for Ripening Tomatoes - 68F to 77F. Tomato ripening is slowed when temperatures are cooler or warmer than the optimum range. Tomatoes stop ripening when temperatures fall below 55F or are greater than 85F. Once tomatoes have begun to blush or turn color, they can be brought to full color or ripeness off the vine at a room temperature of between 70F-75F.

We can’t force the plant to ripen tomatoes on the vine, but there are a few things we can do to help them out. So, if fall is quickly approaching, and you’re stuck wondering how to turn green tomatoes red, then try these six tricks:

1. Cut off the new growth – The growing season is coming to an end, so your plant doesn’t need to waste anymore energy growing new leaves.

Topping the plant and cutting off all the new growth will give it more energy to ripen tomatoes faster.

2. Trim the flowers – Since it takes a couple of months for tomatoes to ripen after the flowers have been pollinated, it’s a pretty sure bet that new flowers aren’t going to amount to anything. So pick off all the flowers.

3. Pinch the suckers – Suckers are the smaller stems that grow between a branches and leaf joint. They get their name because they suck energy from the plant. So be sure to pinch off all of the suckers you see on your tomato plant.

4. Pluck off tiny tomatoes – I know it’s hard to remove any tomatoes from the plant, but these poor little babies won’t have time to mature before frost. Pull them off so your plant can focus on ripening the larger green tomatoes instead.

5. Prune some of the leaves – Don’t cut off all of the leaves, de-leafing tomatoes is never a good idea. But if your plant is huge and full of healthy green leaves, you can trim off much of that vigorous growth. 

6. Reduce water and food late in the season. Reduce water and fertilizer to encourage “mature green” fruits to ripen. Fertilizer–especially excess nitrogen–encourages new leaf growth at the expense of fruit growth and maturation. (Use fertilizer low in nitrogen 4-8-4 for tomatoes.) Reducing water as fruits reach mature size will enhance ripening (and concentrate flavor) and direct the plant’s energy away from new fruit set to ripening fruit already on the vine.