Tomatoes come in a variety of shapes, sizes and colors,
but how do you know if they're ripe?

How do you know when it's ripe?  This is a perennial question asked by beginning gardeners and seasoned gardeners alike, especially when growing a new fruit or vegetable.  In celebration of harvest time, watch for a series of articles on a wide variety of vegetables and fruits commonly grown in home gardens and landscapes.

To start, let's look at tomatoes

For the varieties that turn red, the answer is fairly obvious, but you can ensure that you're getting them at their best if you pick them just as they begin to change from orange to red and then keep them on the kitchen counter or other location with normal light (not in the sun) until they turn that beautiful red color. The reason for picking them early is that the flavor peak will decline if you let it hang on the vine after it turns red.  

Tomatoes of a different color

While red tomatoes are pretty easy to figure out, there many other colors aren't so obvious when they're ripe and ready to enjoy. As a general rule, a ripe tomato will seem heavy for its size and it will be slightly soft, but not mushy, when you gently squeeze it with your fingers.

Green tomatoes - These tomatoes actually get a golden hue when ripe, although they remain green inside. The popular heirloom, the green zebra retains is green zebra-like stripes when ripe.

Purple tomatoes -  Unusual for the deep purple/red hue of its fruit, it was one of the first in the "black" tomato color group and is very popular for its flavor. When ripe they still have green "shoulders" across the top, although the depth of the green color will vary from variety to variety.

White tomatoes - Most are ivory to white and have a bit of give when ripe. They also tend to be a bit transluscent. This is one that you may need to test by picking and slicing it when you think it's ready.  

Orange and yellow tomatoes - Make sure all (or at least most) traces of green are gone and the color is fairly uniform.  For example, a yellow pear tomato turns a sunny yellow color when ripe.

One final note on picking and using fresh tomatoes, never store them in the refrigerator because temperatures below 50 degrees degrade the flavor and long wait for them to ripen will be for nothing.

Photo from Help for Gardeners