You might have to cut into one and look. As the eggplant fruits develop and first fill out, the seed cannot be seen yet, explained Bill Mansour, vegetable crop scientist with the Oregon State University Extension Service. The time to harvest is when the skin is glossy, but not too thick, the flesh is creamy white and the seeds are not yet visible. The seeds become more obvious as the fruit matures. They build up bitter chemicals and the skin gets tough with age.
Eggplants are in the same family as tomatoes and peppers.
Once an eggplant's ovary is fertilized, it enlarges to form the eggplant, explained Mansour. The male anthers simply dry up and disappear.