Because the original color of this tomato is green it can be difficult to tell when it is ripe. There are three main ways to decipher when Green Zebra tomatoes are ready to eat. First, one can grasp the tomato gently to feel for firmness. Secondly, one can tell by looking at when the Zebra’s light green stripes turn to yellow. Thirdly, one can look at when the bottom of the yellow stripes begin to turn a blush color. Each of these stages represents a different ripening stage, so one must decide which stage of ripeness one prefers. Additionally, for a sweeter tomato leave it on the vine for a longer period of time. However, leaving it on the vine for too long can cause it to become mealy.