Does green mean go for tomatoes?

This time of year tends to bring discussion on how to pick a watermelon, but this year the topic seems to have changed to tomatoes.

Do you pick a tomato at the first sign of color and let it ripen on the kitchen counter? Or do you leave it on the vine till it is ready to slice and put on the table? Or somewhere in between?

This decision, like a many things in the garden, depends on personal taste and, of course, is heavily influenced by opinion. As I was reading up on the subject, I found there is a lot of support for both picking early and leaving the tomatoes on the vine. Here are a few pointers to help you get the best-tasting tomatoes as a reward for all your hard work.

Some gardeners argue you should pick tomatoes before they become fully ripe. They claim tomatoes ripen just as well off the vine as long as they are picked in a "mature green" state, which means the seeds inside the fruit are fully developed. Since judging whether the seeds are fully developed is a little hard for most backyard tomato growers, it's sufficient to say green tomatoes may be picked once they've reached their maximum size and have begun to show the first blush of color on their skin.

Horticulturists at Texas A&M say you can increase the size of your tomato harvest if you pick tomatoes before they are entirely ripe. Harvesting the fruits before they are completely ripe tricks the tomato plant into thinking it needs to produce more.

Indeterminate tomato varieties that produce tomatoes all season will slow down production of new blossoms if too many tomatoes are present and ripening. It is known as "fruit load" or "fruit overload," and it can impact your overall harvest.

Another argument in favor of harvesting the tomatoes before they are completely ripe is doing so protects them from becoming damaged from insects, animals, sun-spots, and even wind or summer storms. A ripening tomato is an open invitation to all of the above. Pests, especially birds, are likely to go after fully ripe tomatoes and might get to them before you can pick the fruits.

If you decide this is the method for you, here are some tips for ripening your tomatoes. First of all, keep it out of the fridge and out of the sun. Once the tomato has begun the ripening process, it does not need sunlight to ripen. In fact, too much sun can blister and even injure the fruit. That is exactly what happens when over-ripe tomatoes split open on the vine. Putting those tomatoes on a sunny windowsill can cause the same issue.

As it turns out, tomatoes ripen best when stored in a cool, shady location. The ideal temperature for ripening is actually around 65-70 degrees, with plenty of air circulation.

Now the other side of the coin. Some people argue letting tomatoes fully ripen before picking them leads to the best tasting fruit. There's a scientific reason for this: If you pick a tomato before it's fully ripe, you cut off its supply of oxygen from the main plant.

The not-quite-ripe fruit will continue to ripen after being picked. But, the sugars that develop in the tomato do not have the oxygen they need. Without a supply of oxygen, the sugars easily turn into decay-promoting compounds, such as sugar alcohols and ketones. The decaying sugars can negatively affect the taste of the tomato when it does finish ripening.

For that reason, some gardeners prefer to wait to pick tomatoes until they are fully ripe.

Ultimately, flavor and texture are the best indicators for ripening on the vine. Sample a tomato you think is ripe. If it needs more or less time on the vine, then adjust your harvesting for that variety and that plant accordingly.

If ripening on the vine is your choice, keep an eye on all your tomatoes daily so you can harvest them when they're evenly-colored, firm to the touch with a bit of give on the vine, flavorful and fresh!

My wife and I are still trying to figure out which method best suits us. Good luck with your investigation.

Happy gardening!

Peter Sutter is a lifelong gardening enthusiast and a participant in the University of Missouri Extension's Callaway County Master Gardener Program. Gardening questions can be sent to [email protected].